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 }
84 static int init_hostname (void)
85 {
86 const char *str;
88 struct addrinfo ai_hints;
89 struct addrinfo *ai_list;
90 struct addrinfo *ai_ptr;
91 int status;
93 str = global_option_get ("Hostname");
94 if (str != NULL)
95 {
96 sstrncpy (hostname_g, str, sizeof (hostname_g));
97 return (0);
98 }
100 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
101 {
102 fprintf (stderr, "`gethostname' failed and no "
103 "hostname was configured.\n");
104 return (-1);
105 }
107 str = global_option_get ("FQDNLookup");
108 if (IS_FALSE (str))
109 return (0);
111 memset (&ai_hints, '\0', sizeof (ai_hints));
112 ai_hints.ai_flags = AI_CANONNAME;
114 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
115 if (status != 0)
116 {
117 ERROR ("Looking up \"%s\" failed. You have set the "
118 "\"FQDNLookup\" option, but I cannot resolve "
119 "my hostname to a fully qualified domain "
120 "name. Please fix you network "
121 "configuration.", hostname_g);
122 return (-1);
123 }
125 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
126 {
127 if (ai_ptr->ai_canonname == NULL)
128 continue;
130 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
131 break;
132 }
134 freeaddrinfo (ai_list);
135 return (0);
136 } /* int init_hostname */
138 static int init_global_variables (void)
139 {
140 const char *str;
142 str = global_option_get ("Interval");
143 if (str == NULL)
144 {
145 interval_g = TIME_T_TO_CDTIME_T (10);
146 }
147 else
148 {
149 double tmp;
151 tmp = atof (str);
152 if (tmp <= 0.0)
153 {
154 fprintf (stderr, "Cannot set the interval to a "
155 "correct value.\n"
156 "Please check your settings.\n");
157 return (-1);
158 }
160 interval_g = DOUBLE_TO_CDTIME_T (tmp);
161 }
162 DEBUG ("interval_g = %.3f;", CDTIME_T_TO_DOUBLE (interval_g));
164 str = global_option_get ("Timeout");
165 if (str == NULL)
166 str = "2";
167 timeout_g = atoi (str);
168 if (timeout_g <= 1)
169 {
170 fprintf (stderr, "Cannot set the timeout to a correct value.\n"
171 "Please check your settings.\n");
172 return (-1);
173 }
174 DEBUG ("timeout_g = %i;", timeout_g);
176 if (init_hostname () != 0)
177 return (-1);
178 DEBUG ("hostname_g = %s;", hostname_g);
180 return (0);
181 } /* int init_global_variables */
183 static int change_basedir (const char *orig_dir)
184 {
185 char *dir;
186 size_t dirlen;
187 int status;
189 dir = strdup (orig_dir);
190 if (dir == NULL)
191 {
192 char errbuf[1024];
193 ERROR ("strdup failed: %s",
194 sstrerror (errno, errbuf, sizeof (errbuf)));
195 return (-1);
196 }
198 dirlen = strlen (dir);
199 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
200 dir[--dirlen] = '\0';
202 if (dirlen <= 0)
203 return (-1);
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" [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" "VERSION", http://collectd.org/\n"
295 "by Florian octo Forster <octo@verplant.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_LIBKSTAT
303 kc = NULL;
304 update_kstat ();
305 #endif
307 #if HAVE_LIBSTATGRAB
308 if (sg_init ())
309 {
310 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
311 return (-1);
312 }
314 if (sg_drop_privileges ())
315 {
316 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
317 return (-1);
318 }
319 #endif
321 plugin_init_all ();
323 return (0);
324 } /* int do_init () */
327 static int do_loop (void)
328 {
329 cdtime_t wait_until;
331 wait_until = cdtime () + interval_g;
333 while (loop == 0)
334 {
335 struct timespec ts_wait = { 0, 0 };
336 cdtime_t now;
338 #if HAVE_LIBKSTAT
339 update_kstat ();
340 #endif
342 /* Issue all plugins */
343 plugin_read_all ();
345 now = cdtime ();
346 if (now >= wait_until)
347 {
348 WARNING ("Not sleeping because the next interval is "
349 "%.3f seconds in the past!",
350 CDTIME_T_TO_DOUBLE (now - wait_until));
351 wait_until = now + interval_g;
352 continue;
353 }
355 CDTIME_T_TO_TIMESPEC (wait_until - now, &ts_wait);
356 wait_until = wait_until + interval_g;
358 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) != 0))
359 {
360 if (errno != EINTR)
361 {
362 char errbuf[1024];
363 ERROR ("nanosleep failed: %s",
364 sstrerror (errno, errbuf,
365 sizeof (errbuf)));
366 return (-1);
367 }
368 }
369 } /* while (loop == 0) */
371 return (0);
372 } /* int do_loop */
374 static int do_shutdown (void)
375 {
376 plugin_shutdown_all ();
377 return (0);
378 } /* int do_shutdown */
380 #if COLLECT_DAEMON
381 static int pidfile_create (void)
382 {
383 FILE *fh;
384 const char *file = global_option_get ("PIDFile");
386 if ((fh = fopen (file, "w")) == NULL)
387 {
388 char errbuf[1024];
389 ERROR ("fopen (%s): %s", file,
390 sstrerror (errno, errbuf, sizeof (errbuf)));
391 return (1);
392 }
394 fprintf (fh, "%i\n", (int) getpid ());
395 fclose(fh);
397 return (0);
398 } /* static int pidfile_create (const char *file) */
400 static int pidfile_remove (void)
401 {
402 const char *file = global_option_get ("PIDFile");
404 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
405 return (unlink (file));
406 } /* static int pidfile_remove (const char *file) */
407 #endif /* COLLECT_DAEMON */
409 int main (int argc, char **argv)
410 {
411 struct sigaction sig_int_action;
412 struct sigaction sig_term_action;
413 struct sigaction sig_usr1_action;
414 struct sigaction sig_pipe_action;
415 char *configfile = CONFIGFILE;
416 int test_config = 0;
417 int test_readall = 0;
418 const char *basedir;
419 #if COLLECT_DAEMON
420 struct sigaction sig_chld_action;
421 pid_t pid;
422 int daemonize = 1;
423 #endif
424 int exit_status = 0;
426 /* read options */
427 while (1)
428 {
429 int c;
431 c = getopt (argc, argv, "htTC:"
432 #if COLLECT_DAEMON
433 "fP:"
434 #endif
435 );
437 if (c == -1)
438 break;
440 switch (c)
441 {
442 case 'C':
443 configfile = optarg;
444 break;
445 case 't':
446 test_config = 1;
447 break;
448 case 'T':
449 test_readall = 1;
450 global_option_set ("ReadThreads", "-1");
451 #if COLLECT_DAEMON
452 daemonize = 0;
453 #endif /* COLLECT_DAEMON */
454 break;
455 #if COLLECT_DAEMON
456 case 'P':
457 global_option_set ("PIDFile", optarg);
458 break;
459 case 'f':
460 daemonize = 0;
461 break;
462 #endif /* COLLECT_DAEMON */
463 case 'h':
464 exit_usage (0);
465 break;
466 default:
467 exit_usage (1);
468 } /* switch (c) */
469 } /* while (1) */
471 if (optind < argc)
472 exit_usage (1);
474 /*
475 * Read options from the config file, the environment and the command
476 * line (in that order, with later options overwriting previous ones in
477 * general).
478 * Also, this will automatically load modules.
479 */
480 if (cf_read (configfile))
481 {
482 fprintf (stderr, "Error: Reading the config file failed!\n"
483 "Read the syslog for details.\n");
484 return (1);
485 }
487 /*
488 * Change directory. We do this _after_ reading the config and loading
489 * modules to relative paths work as expected.
490 */
491 if ((basedir = global_option_get ("BaseDir")) == NULL)
492 {
493 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
494 return (1);
495 }
496 else if (change_basedir (basedir))
497 {
498 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
499 return (1);
500 }
502 /*
503 * Set global variables or, if that failes, exit. We cannot run with
504 * them being uninitialized. If nothing is configured, then defaults
505 * are being used. So this means that the user has actually done
506 * something wrong.
507 */
508 if (init_global_variables () != 0)
509 return (1);
511 if (test_config)
512 return (0);
514 #if COLLECT_DAEMON
515 /*
516 * fork off child
517 */
518 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
519 sig_chld_action.sa_handler = SIG_IGN;
520 sigaction (SIGCHLD, &sig_chld_action, NULL);
522 if (daemonize)
523 {
524 if ((pid = fork ()) == -1)
525 {
526 /* error */
527 char errbuf[1024];
528 fprintf (stderr, "fork: %s",
529 sstrerror (errno, errbuf,
530 sizeof (errbuf)));
531 return (1);
532 }
533 else if (pid != 0)
534 {
535 /* parent */
536 /* printf ("Running (PID %i)\n", pid); */
537 return (0);
538 }
540 /* Detach from session */
541 setsid ();
543 /* Write pidfile */
544 if (pidfile_create ())
545 exit (2);
547 /* close standard descriptors */
548 close (2);
549 close (1);
550 close (0);
552 if (open ("/dev/null", O_RDWR) != 0)
553 {
554 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
555 return (1);
556 }
557 if (dup (0) != 1)
558 {
559 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
560 return (1);
561 }
562 if (dup (0) != 2)
563 {
564 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
565 return (1);
566 }
567 } /* if (daemonize) */
568 #endif /* COLLECT_DAEMON */
570 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
571 sig_pipe_action.sa_handler = SIG_IGN;
572 sigaction (SIGPIPE, &sig_pipe_action, NULL);
574 /*
575 * install signal handlers
576 */
577 memset (&sig_int_action, '\0', sizeof (sig_int_action));
578 sig_int_action.sa_handler = sig_int_handler;
579 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
580 char errbuf[1024];
581 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
582 sstrerror (errno, errbuf, sizeof (errbuf)));
583 return (1);
584 }
586 memset (&sig_term_action, '\0', sizeof (sig_term_action));
587 sig_term_action.sa_handler = sig_term_handler;
588 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
589 char errbuf[1024];
590 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
591 sstrerror (errno, errbuf, sizeof (errbuf)));
592 return (1);
593 }
595 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
596 sig_usr1_action.sa_handler = sig_usr1_handler;
597 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
598 char errbuf[1024];
599 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
600 sstrerror (errno, errbuf, sizeof (errbuf)));
601 return (1);
602 }
604 /*
605 * run the actual loops
606 */
607 do_init ();
609 if (test_readall)
610 {
611 if (plugin_read_all_once () != 0)
612 exit_status = 1;
613 }
614 else
615 {
616 INFO ("Initialization complete, entering read-loop.");
617 do_loop ();
618 }
620 /* close syslog */
621 INFO ("Exiting normally.");
623 do_shutdown ();
625 #if COLLECT_DAEMON
626 if (daemonize)
627 pidfile_remove ();
628 #endif /* COLLECT_DAEMON */
630 return (exit_status);
631 } /* int main */