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 #if HAVE_LIBKSTAT
45 kstat_ctl_t *kc;
46 #endif /* HAVE_LIBKSTAT */
48 static int loop = 0;
50 static void *do_flush (void __attribute__((unused)) *arg)
51 {
52 INFO ("Flushing all data.");
53 plugin_flush (NULL, -1, NULL);
54 INFO ("Finished flushing all data.");
55 pthread_exit (NULL);
56 return NULL;
57 }
59 static void sig_int_handler (int __attribute__((unused)) signal)
60 {
61 loop++;
62 }
64 static void sig_term_handler (int __attribute__((unused)) signal)
65 {
66 loop++;
67 }
69 static void sig_usr1_handler (int __attribute__((unused)) signal)
70 {
71 pthread_t thread;
72 pthread_attr_t attr;
74 /* flushing the data might take a while,
75 * so it should be done asynchronously */
76 pthread_attr_init (&attr);
77 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
78 pthread_create (&thread, &attr, do_flush, NULL);
79 }
81 static int init_hostname (void)
82 {
83 const char *str;
85 struct addrinfo ai_hints;
86 struct addrinfo *ai_list;
87 struct addrinfo *ai_ptr;
88 int status;
90 str = global_option_get ("Hostname");
91 if (str != NULL)
92 {
93 sstrncpy (hostname_g, str, sizeof (hostname_g));
94 return (0);
95 }
97 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
98 {
99 fprintf (stderr, "`gethostname' failed and no "
100 "hostname was configured.\n");
101 return (-1);
102 }
104 str = global_option_get ("FQDNLookup");
105 if (IS_FALSE (str))
106 return (0);
108 memset (&ai_hints, '\0', sizeof (ai_hints));
109 ai_hints.ai_flags = AI_CANONNAME;
111 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
112 if (status != 0)
113 {
114 ERROR ("Looking up \"%s\" failed. You have set the "
115 "\"FQDNLookup\" option, but I cannot resolve "
116 "my hostname to a fully qualified domain "
117 "name. Please fix you network "
118 "configuration.", hostname_g);
119 return (-1);
120 }
122 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
123 {
124 if (ai_ptr->ai_canonname == NULL)
125 continue;
127 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
128 break;
129 }
131 freeaddrinfo (ai_list);
132 return (0);
133 } /* int init_hostname */
135 static int init_global_variables (void)
136 {
137 const char *str;
139 str = global_option_get ("Interval");
140 if (str == NULL)
141 str = "10";
142 interval_g = atoi (str);
143 if (interval_g <= 0)
144 {
145 fprintf (stderr, "Cannot set the interval to a correct value.\n"
146 "Please check your settings.\n");
147 return (-1);
148 }
149 DEBUG ("interval_g = %i;", interval_g);
151 if (init_hostname () != 0)
152 return (-1);
153 DEBUG ("hostname_g = %s;", hostname_g);
155 return (0);
156 } /* int init_global_variables */
158 static int change_basedir (const char *orig_dir)
159 {
160 char *dir = strdup (orig_dir);
161 int dirlen;
162 int status;
164 if (dir == NULL)
165 {
166 char errbuf[1024];
167 ERROR ("strdup failed: %s",
168 sstrerror (errno, errbuf, sizeof (errbuf)));
169 return (-1);
170 }
172 dirlen = strlen (dir);
173 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
174 dir[--dirlen] = '\0';
176 if (dirlen <= 0)
177 return (-1);
179 status = chdir (dir);
180 free (dir);
182 if (status != 0)
183 {
184 if (errno == ENOENT)
185 {
186 if (mkdir (orig_dir, 0755) == -1)
187 {
188 char errbuf[1024];
189 ERROR ("change_basedir: mkdir (%s): %s", orig_dir,
190 sstrerror (errno, errbuf,
191 sizeof (errbuf)));
192 return (-1);
193 }
194 else if (chdir (orig_dir) == -1)
195 {
196 char errbuf[1024];
197 ERROR ("chdir (%s): %s", orig_dir,
198 sstrerror (errno, errbuf,
199 sizeof (errbuf)));
200 return (-1);
201 }
202 }
203 else
204 {
205 char errbuf[1024];
206 ERROR ("chdir (%s): %s", orig_dir,
207 sstrerror (errno, errbuf,
208 sizeof (errbuf)));
209 return (-1);
210 }
211 }
213 return (0);
214 } /* static int change_basedir (char *dir) */
216 #if HAVE_LIBKSTAT
217 static void update_kstat (void)
218 {
219 if (kc == NULL)
220 {
221 if ((kc = kstat_open ()) == NULL)
222 ERROR ("Unable to open kstat control structure");
223 }
224 else
225 {
226 kid_t kid;
227 kid = kstat_chain_update (kc);
228 if (kid > 0)
229 {
230 INFO ("kstat chain has been updated");
231 plugin_init_all ();
232 }
233 else if (kid < 0)
234 ERROR ("kstat chain update failed");
235 /* else: everything works as expected */
236 }
238 return;
239 } /* static void update_kstat (void) */
240 #endif /* HAVE_LIBKSTAT */
242 /* TODO
243 * Remove all settings but `-f' and `-C'
244 */
245 static void exit_usage (int status)
246 {
247 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
249 "Available options:\n"
250 " General:\n"
251 " -C <file> Configuration file.\n"
252 " Default: "CONFIGFILE"\n"
253 " -t Test config and exit.\n"
254 " -T Test plugin read and exit.\n"
255 " -P <file> PID-file.\n"
256 " Default: "PIDFILE"\n"
257 #if COLLECT_DAEMON
258 " -f Don't fork to the background.\n"
259 #endif
260 " -h Display help (this message)\n"
261 "\nBuiltin defaults:\n"
262 " Config-File "CONFIGFILE"\n"
263 " PID-File "PIDFILE"\n"
264 " Data-Directory "PKGLOCALSTATEDIR"\n"
265 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
266 "by Florian octo Forster <octo@verplant.org>\n"
267 "for contributions see `AUTHORS'\n");
268 exit (status);
269 } /* static void exit_usage (int status) */
271 static int do_init (void)
272 {
273 #if HAVE_LIBKSTAT
274 kc = NULL;
275 update_kstat ();
276 #endif
278 #if HAVE_LIBSTATGRAB
279 if (sg_init ())
280 {
281 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
282 return (-1);
283 }
285 if (sg_drop_privileges ())
286 {
287 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
288 return (-1);
289 }
290 #endif
292 plugin_init_all ();
294 return (0);
295 } /* int do_init () */
298 static int do_loop (void)
299 {
300 struct timeval tv_now;
301 struct timeval tv_next;
302 struct timeval tv_wait;
303 struct timespec ts_wait;
305 while (loop == 0)
306 {
307 if (gettimeofday (&tv_next, NULL) < 0)
308 {
309 char errbuf[1024];
310 ERROR ("gettimeofday failed: %s",
311 sstrerror (errno, errbuf,
312 sizeof (errbuf)));
313 return (-1);
314 }
315 tv_next.tv_sec += interval_g;
317 #if HAVE_LIBKSTAT
318 update_kstat ();
319 #endif
321 /* Issue all plugins */
322 plugin_read_all ();
324 if (gettimeofday (&tv_now, NULL) < 0)
325 {
326 char errbuf[1024];
327 ERROR ("gettimeofday failed: %s",
328 sstrerror (errno, errbuf,
329 sizeof (errbuf)));
330 return (-1);
331 }
333 if (timeval_cmp (tv_next, tv_now, &tv_wait) <= 0)
334 {
335 WARNING ("Not sleeping because the next interval is "
336 "%i.%06i seconds in the past!",
337 (int) tv_wait.tv_sec, (int) tv_wait.tv_usec);
338 continue;
339 }
341 ts_wait.tv_sec = tv_wait.tv_sec;
342 ts_wait.tv_nsec = (long) (1000 * tv_wait.tv_usec);
344 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
345 {
346 if (errno != EINTR)
347 {
348 char errbuf[1024];
349 ERROR ("nanosleep failed: %s",
350 sstrerror (errno, errbuf,
351 sizeof (errbuf)));
352 return (-1);
353 }
354 }
355 } /* while (loop == 0) */
357 DEBUG ("return (0);");
358 return (0);
359 } /* int do_loop */
361 static int do_shutdown (void)
362 {
363 plugin_shutdown_all ();
364 return (0);
365 } /* int do_shutdown */
367 #if COLLECT_DAEMON
368 static int pidfile_create (void)
369 {
370 FILE *fh;
371 const char *file = global_option_get ("PIDFile");
373 if ((fh = fopen (file, "w")) == NULL)
374 {
375 char errbuf[1024];
376 ERROR ("fopen (%s): %s", file,
377 sstrerror (errno, errbuf, sizeof (errbuf)));
378 return (1);
379 }
381 fprintf (fh, "%i\n", (int) getpid ());
382 fclose(fh);
384 return (0);
385 } /* static int pidfile_create (const char *file) */
387 static int pidfile_remove (void)
388 {
389 const char *file = global_option_get ("PIDFile");
391 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
392 return (unlink (file));
393 } /* static int pidfile_remove (const char *file) */
394 #endif /* COLLECT_DAEMON */
396 int main (int argc, char **argv)
397 {
398 struct sigaction sig_int_action;
399 struct sigaction sig_term_action;
400 struct sigaction sig_usr1_action;
401 struct sigaction sig_pipe_action;
402 char *configfile = CONFIGFILE;
403 int test_config = 0;
404 int test_readall = 0;
405 const char *basedir;
406 #if COLLECT_DAEMON
407 struct sigaction sig_chld_action;
408 pid_t pid;
409 int daemonize = 1;
410 #endif
411 int exit_status = 0;
413 /* read options */
414 while (1)
415 {
416 int c;
418 c = getopt (argc, argv, "htTC:"
419 #if COLLECT_DAEMON
420 "fP:"
421 #endif
422 );
424 if (c == -1)
425 break;
427 switch (c)
428 {
429 case 'C':
430 configfile = optarg;
431 break;
432 case 't':
433 test_config = 1;
434 break;
435 case 'T':
436 test_readall = 1;
437 global_option_set ("ReadThreads", "-1");
438 #if COLLECT_DAEMON
439 daemonize = 0;
440 #endif /* COLLECT_DAEMON */
441 break;
442 #if COLLECT_DAEMON
443 case 'P':
444 global_option_set ("PIDFile", optarg);
445 break;
446 case 'f':
447 daemonize = 0;
448 break;
449 #endif /* COLLECT_DAEMON */
450 case 'h':
451 exit_usage (0);
452 break;
453 default:
454 exit_usage (1);
455 } /* switch (c) */
456 } /* while (1) */
458 if (optind < argc)
459 exit_usage (1);
461 /*
462 * Read options from the config file, the environment and the command
463 * line (in that order, with later options overwriting previous ones in
464 * general).
465 * Also, this will automatically load modules.
466 */
467 if (cf_read (configfile))
468 {
469 fprintf (stderr, "Error: Reading the config file failed!\n"
470 "Read the syslog for details.\n");
471 return (1);
472 }
474 /*
475 * Change directory. We do this _after_ reading the config and loading
476 * modules to relative paths work as expected.
477 */
478 if ((basedir = global_option_get ("BaseDir")) == NULL)
479 {
480 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
481 return (1);
482 }
483 else if (change_basedir (basedir))
484 {
485 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
486 return (1);
487 }
489 /*
490 * Set global variables or, if that failes, exit. We cannot run with
491 * them being uninitialized. If nothing is configured, then defaults
492 * are being used. So this means that the user has actually done
493 * something wrong.
494 */
495 if (init_global_variables () != 0)
496 return (1);
498 if (test_config)
499 return (0);
501 #if COLLECT_DAEMON
502 /*
503 * fork off child
504 */
505 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
506 sig_chld_action.sa_handler = SIG_IGN;
507 sigaction (SIGCHLD, &sig_chld_action, NULL);
509 if (daemonize)
510 {
511 if ((pid = fork ()) == -1)
512 {
513 /* error */
514 char errbuf[1024];
515 fprintf (stderr, "fork: %s",
516 sstrerror (errno, errbuf,
517 sizeof (errbuf)));
518 return (1);
519 }
520 else if (pid != 0)
521 {
522 /* parent */
523 /* printf ("Running (PID %i)\n", pid); */
524 return (0);
525 }
527 /* Detach from session */
528 setsid ();
530 /* Write pidfile */
531 if (pidfile_create ())
532 exit (2);
534 /* close standard descriptors */
535 close (2);
536 close (1);
537 close (0);
539 if (open ("/dev/null", O_RDWR) != 0)
540 {
541 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
542 return (1);
543 }
544 if (dup (0) != 1)
545 {
546 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
547 return (1);
548 }
549 if (dup (0) != 2)
550 {
551 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
552 return (1);
553 }
554 } /* if (daemonize) */
555 #endif /* COLLECT_DAEMON */
557 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
558 sig_pipe_action.sa_handler = SIG_IGN;
559 sigaction (SIGPIPE, &sig_pipe_action, NULL);
561 /*
562 * install signal handlers
563 */
564 memset (&sig_int_action, '\0', sizeof (sig_int_action));
565 sig_int_action.sa_handler = sig_int_handler;
566 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
567 char errbuf[1024];
568 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
569 sstrerror (errno, errbuf, sizeof (errbuf)));
570 return (1);
571 }
573 memset (&sig_term_action, '\0', sizeof (sig_term_action));
574 sig_term_action.sa_handler = sig_term_handler;
575 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
576 char errbuf[1024];
577 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
578 sstrerror (errno, errbuf, sizeof (errbuf)));
579 return (1);
580 }
582 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
583 sig_usr1_action.sa_handler = sig_usr1_handler;
584 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
585 char errbuf[1024];
586 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
587 sstrerror (errno, errbuf, sizeof (errbuf)));
588 return (1);
589 }
591 /*
592 * run the actual loops
593 */
594 do_init ();
596 if (test_readall)
597 {
598 if (plugin_read_all_once () != 0)
599 exit_status = 1;
600 }
601 else
602 {
603 INFO ("Initialization complete, entering read-loop.");
604 do_loop ();
605 }
607 /* close syslog */
608 INFO ("Exiting normally.");
610 do_shutdown ();
612 #if COLLECT_DAEMON
613 if (daemonize)
614 pidfile_remove ();
615 #endif /* COLLECT_DAEMON */
617 return (exit_status);
618 } /* int main */