b68aea5ca9ce894b5b7d7c13289726e3bc11a4d9
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 }
82 static int init_hostname (void)
83 {
84 const char *str;
86 struct addrinfo ai_hints;
87 struct addrinfo *ai_list;
88 struct addrinfo *ai_ptr;
89 int status;
91 str = global_option_get ("Hostname");
92 if (str != NULL)
93 {
94 sstrncpy (hostname_g, str, sizeof (hostname_g));
95 return (0);
96 }
98 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
99 {
100 fprintf (stderr, "`gethostname' failed and no "
101 "hostname was configured.\n");
102 return (-1);
103 }
105 str = global_option_get ("FQDNLookup");
106 if (IS_FALSE (str))
107 return (0);
109 memset (&ai_hints, '\0', sizeof (ai_hints));
110 ai_hints.ai_flags = AI_CANONNAME;
112 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
113 if (status != 0)
114 {
115 ERROR ("Looking up \"%s\" failed. You have set the "
116 "\"FQDNLookup\" option, but I cannot resolve "
117 "my hostname to a fully qualified domain "
118 "name. Please fix you network "
119 "configuration.", hostname_g);
120 return (-1);
121 }
123 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
124 {
125 if (ai_ptr->ai_canonname == NULL)
126 continue;
128 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
129 break;
130 }
132 freeaddrinfo (ai_list);
133 return (0);
134 } /* int init_hostname */
136 static int init_global_variables (void)
137 {
138 const char *str;
140 str = global_option_get ("Interval");
141 if (str == NULL)
142 str = "10";
143 interval_g = atoi (str);
144 if (interval_g <= 0)
145 {
146 fprintf (stderr, "Cannot set the interval to a correct value.\n"
147 "Please check your settings.\n");
148 return (-1);
149 }
150 DEBUG ("interval_g = %i;", interval_g);
152 str = global_option_get ("Timeout");
153 if (str == NULL)
154 str = "2";
155 timeout_g = atoi (str);
156 if (timeout_g <= 1)
157 {
158 fprintf (stderr, "Cannot set the timeout to a correct value.\n"
159 "Please check your settings.\n");
160 return (-1);
161 }
162 DEBUG ("timeout_g = %i;", timeout_g);
164 if (init_hostname () != 0)
165 return (-1);
166 DEBUG ("hostname_g = %s;", hostname_g);
168 return (0);
169 } /* int init_global_variables */
171 static int change_basedir (const char *orig_dir)
172 {
173 char *dir;
174 size_t dirlen;
175 int status;
177 dir = strdup (orig_dir);
178 if (dir == NULL)
179 {
180 char errbuf[1024];
181 ERROR ("strdup failed: %s",
182 sstrerror (errno, errbuf, sizeof (errbuf)));
183 return (-1);
184 }
186 dirlen = strlen (dir);
187 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
188 dir[--dirlen] = '\0';
190 if (dirlen <= 0)
191 return (-1);
193 status = chdir (dir);
194 if (status == 0)
195 {
196 free (dir);
197 return (0);
198 }
199 else if (errno != ENOENT)
200 {
201 char errbuf[1024];
202 ERROR ("change_basedir: chdir (%s): %s", dir,
203 sstrerror (errno, errbuf, sizeof (errbuf)));
204 free (dir);
205 return (-1);
206 }
208 status = mkdir (dir, S_IRWXU | S_IRWXG | S_IRWXO);
209 if (status != 0)
210 {
211 char errbuf[1024];
212 ERROR ("change_basedir: mkdir (%s): %s", dir,
213 sstrerror (errno, errbuf, sizeof (errbuf)));
214 free (dir);
215 return (-1);
216 }
218 status = chdir (dir);
219 if (status != 0)
220 {
221 char errbuf[1024];
222 ERROR ("change_basedir: chdir (%s): %s", dir,
223 sstrerror (errno, errbuf, sizeof (errbuf)));
224 free (dir);
225 return (-1);
226 }
228 free (dir);
229 return (0);
230 } /* static int change_basedir (char *dir) */
232 #if HAVE_LIBKSTAT
233 static void update_kstat (void)
234 {
235 if (kc == NULL)
236 {
237 if ((kc = kstat_open ()) == NULL)
238 ERROR ("Unable to open kstat control structure");
239 }
240 else
241 {
242 kid_t kid;
243 kid = kstat_chain_update (kc);
244 if (kid > 0)
245 {
246 INFO ("kstat chain has been updated");
247 plugin_init_all ();
248 }
249 else if (kid < 0)
250 ERROR ("kstat chain update failed");
251 /* else: everything works as expected */
252 }
254 return;
255 } /* static void update_kstat (void) */
256 #endif /* HAVE_LIBKSTAT */
258 /* TODO
259 * Remove all settings but `-f' and `-C'
260 */
261 static void exit_usage (int status)
262 {
263 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
265 "Available options:\n"
266 " General:\n"
267 " -C <file> Configuration file.\n"
268 " Default: "CONFIGFILE"\n"
269 " -t Test config and exit.\n"
270 " -T Test plugin read and exit.\n"
271 " -P <file> PID-file.\n"
272 " Default: "PIDFILE"\n"
273 #if COLLECT_DAEMON
274 " -f Don't fork to the background.\n"
275 #endif
276 " -h Display help (this message)\n"
277 "\nBuiltin defaults:\n"
278 " Config file "CONFIGFILE"\n"
279 " PID file "PIDFILE"\n"
280 " Plugin directory "PLUGINDIR"\n"
281 " Data directory "PKGLOCALSTATEDIR"\n"
282 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
283 "by Florian octo Forster <octo@verplant.org>\n"
284 "for contributions see `AUTHORS'\n");
285 exit (status);
286 } /* static void exit_usage (int status) */
288 static int do_init (void)
289 {
290 #if HAVE_LIBKSTAT
291 kc = NULL;
292 update_kstat ();
293 #endif
295 #if HAVE_LIBSTATGRAB
296 if (sg_init ())
297 {
298 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
299 return (-1);
300 }
302 if (sg_drop_privileges ())
303 {
304 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
305 return (-1);
306 }
307 #endif
309 plugin_init_all ();
311 return (0);
312 } /* int do_init () */
315 static int do_loop (void)
316 {
317 struct timeval tv_now;
318 struct timeval tv_next;
319 struct timeval tv_wait;
320 struct timespec ts_wait;
322 while (loop == 0)
323 {
324 if (gettimeofday (&tv_next, NULL) < 0)
325 {
326 char errbuf[1024];
327 ERROR ("gettimeofday failed: %s",
328 sstrerror (errno, errbuf,
329 sizeof (errbuf)));
330 return (-1);
331 }
332 tv_next.tv_sec += interval_g;
334 #if HAVE_LIBKSTAT
335 update_kstat ();
336 #endif
338 /* Issue all plugins */
339 plugin_read_all ();
341 if (gettimeofday (&tv_now, NULL) < 0)
342 {
343 char errbuf[1024];
344 ERROR ("gettimeofday failed: %s",
345 sstrerror (errno, errbuf,
346 sizeof (errbuf)));
347 return (-1);
348 }
350 if (timeval_cmp (tv_next, tv_now, &tv_wait) <= 0)
351 {
352 WARNING ("Not sleeping because the next interval is "
353 "%i.%06i seconds in the past!",
354 (int) tv_wait.tv_sec, (int) tv_wait.tv_usec);
355 continue;
356 }
358 ts_wait.tv_sec = tv_wait.tv_sec;
359 ts_wait.tv_nsec = (long) (1000 * tv_wait.tv_usec);
361 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
362 {
363 if (errno != EINTR)
364 {
365 char errbuf[1024];
366 ERROR ("nanosleep failed: %s",
367 sstrerror (errno, errbuf,
368 sizeof (errbuf)));
369 return (-1);
370 }
371 }
372 } /* while (loop == 0) */
374 DEBUG ("return (0);");
375 return (0);
376 } /* int do_loop */
378 static int do_shutdown (void)
379 {
380 plugin_shutdown_all ();
381 return (0);
382 } /* int do_shutdown */
384 #if COLLECT_DAEMON
385 static int pidfile_create (void)
386 {
387 FILE *fh;
388 const char *file = global_option_get ("PIDFile");
390 if ((fh = fopen (file, "w")) == NULL)
391 {
392 char errbuf[1024];
393 ERROR ("fopen (%s): %s", file,
394 sstrerror (errno, errbuf, sizeof (errbuf)));
395 return (1);
396 }
398 fprintf (fh, "%i\n", (int) getpid ());
399 fclose(fh);
401 return (0);
402 } /* static int pidfile_create (const char *file) */
404 static int pidfile_remove (void)
405 {
406 const char *file = global_option_get ("PIDFile");
408 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
409 return (unlink (file));
410 } /* static int pidfile_remove (const char *file) */
411 #endif /* COLLECT_DAEMON */
413 int main (int argc, char **argv)
414 {
415 struct sigaction sig_int_action;
416 struct sigaction sig_term_action;
417 struct sigaction sig_usr1_action;
418 struct sigaction sig_pipe_action;
419 char *configfile = CONFIGFILE;
420 int test_config = 0;
421 int test_readall = 0;
422 const char *basedir;
423 #if COLLECT_DAEMON
424 struct sigaction sig_chld_action;
425 pid_t pid;
426 int daemonize = 1;
427 #endif
428 int exit_status = 0;
430 /* read options */
431 while (1)
432 {
433 int c;
435 c = getopt (argc, argv, "htTC:"
436 #if COLLECT_DAEMON
437 "fP:"
438 #endif
439 );
441 if (c == -1)
442 break;
444 switch (c)
445 {
446 case 'C':
447 configfile = optarg;
448 break;
449 case 't':
450 test_config = 1;
451 break;
452 case 'T':
453 test_readall = 1;
454 global_option_set ("ReadThreads", "-1");
455 #if COLLECT_DAEMON
456 daemonize = 0;
457 #endif /* COLLECT_DAEMON */
458 break;
459 #if COLLECT_DAEMON
460 case 'P':
461 global_option_set ("PIDFile", optarg);
462 break;
463 case 'f':
464 daemonize = 0;
465 break;
466 #endif /* COLLECT_DAEMON */
467 case 'h':
468 exit_usage (0);
469 break;
470 default:
471 exit_usage (1);
472 } /* switch (c) */
473 } /* while (1) */
475 if (optind < argc)
476 exit_usage (1);
478 /*
479 * Read options from the config file, the environment and the command
480 * line (in that order, with later options overwriting previous ones in
481 * general).
482 * Also, this will automatically load modules.
483 */
484 if (cf_read (configfile))
485 {
486 fprintf (stderr, "Error: Reading the config file failed!\n"
487 "Read the syslog for details.\n");
488 return (1);
489 }
491 /*
492 * Change directory. We do this _after_ reading the config and loading
493 * modules to relative paths work as expected.
494 */
495 if ((basedir = global_option_get ("BaseDir")) == NULL)
496 {
497 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
498 return (1);
499 }
500 else if (change_basedir (basedir))
501 {
502 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
503 return (1);
504 }
506 /*
507 * Set global variables or, if that failes, exit. We cannot run with
508 * them being uninitialized. If nothing is configured, then defaults
509 * are being used. So this means that the user has actually done
510 * something wrong.
511 */
512 if (init_global_variables () != 0)
513 return (1);
515 if (test_config)
516 return (0);
518 #if COLLECT_DAEMON
519 /*
520 * fork off child
521 */
522 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
523 sig_chld_action.sa_handler = SIG_IGN;
524 sigaction (SIGCHLD, &sig_chld_action, NULL);
526 if (daemonize)
527 {
528 if ((pid = fork ()) == -1)
529 {
530 /* error */
531 char errbuf[1024];
532 fprintf (stderr, "fork: %s",
533 sstrerror (errno, errbuf,
534 sizeof (errbuf)));
535 return (1);
536 }
537 else if (pid != 0)
538 {
539 /* parent */
540 /* printf ("Running (PID %i)\n", pid); */
541 return (0);
542 }
544 /* Detach from session */
545 setsid ();
547 /* Write pidfile */
548 if (pidfile_create ())
549 exit (2);
551 /* close standard descriptors */
552 close (2);
553 close (1);
554 close (0);
556 if (open ("/dev/null", O_RDWR) != 0)
557 {
558 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
559 return (1);
560 }
561 if (dup (0) != 1)
562 {
563 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
564 return (1);
565 }
566 if (dup (0) != 2)
567 {
568 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
569 return (1);
570 }
571 } /* if (daemonize) */
572 #endif /* COLLECT_DAEMON */
574 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
575 sig_pipe_action.sa_handler = SIG_IGN;
576 sigaction (SIGPIPE, &sig_pipe_action, NULL);
578 /*
579 * install signal handlers
580 */
581 memset (&sig_int_action, '\0', sizeof (sig_int_action));
582 sig_int_action.sa_handler = sig_int_handler;
583 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
584 char errbuf[1024];
585 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
586 sstrerror (errno, errbuf, sizeof (errbuf)));
587 return (1);
588 }
590 memset (&sig_term_action, '\0', sizeof (sig_term_action));
591 sig_term_action.sa_handler = sig_term_handler;
592 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
593 char errbuf[1024];
594 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
595 sstrerror (errno, errbuf, sizeof (errbuf)));
596 return (1);
597 }
599 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
600 sig_usr1_action.sa_handler = sig_usr1_handler;
601 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
602 char errbuf[1024];
603 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
604 sstrerror (errno, errbuf, sizeof (errbuf)));
605 return (1);
606 }
608 /*
609 * run the actual loops
610 */
611 do_init ();
613 if (test_readall)
614 {
615 if (plugin_read_all_once () != 0)
616 exit_status = 1;
617 }
618 else
619 {
620 INFO ("Initialization complete, entering read-loop.");
621 do_loop ();
622 }
624 /* close syslog */
625 INFO ("Exiting normally.");
627 do_shutdown ();
629 #if COLLECT_DAEMON
630 if (daemonize)
631 pidfile_remove ();
632 #endif /* COLLECT_DAEMON */
634 return (exit_status);
635 } /* int main */