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 *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 signal)
60 {
61 loop++;
62 }
64 static void sig_term_handler (int signal)
65 {
66 loop++;
67 }
69 static void sig_usr1_handler (int 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 ((strcasecmp ("false", str) == 0)
106 || (strcasecmp ("no", str) == 0)
107 || (strcasecmp ("off", str) == 0))
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 if (init_hostname () != 0)
154 return (-1);
155 DEBUG ("hostname_g = %s;", hostname_g);
157 return (0);
158 } /* int init_global_variables */
160 static int change_basedir (const char *orig_dir)
161 {
162 char *dir = strdup (orig_dir);
163 int dirlen;
164 int status;
166 if (dir == NULL)
167 {
168 char errbuf[1024];
169 ERROR ("strdup failed: %s",
170 sstrerror (errno, errbuf, sizeof (errbuf)));
171 return (-1);
172 }
174 dirlen = strlen (dir);
175 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
176 dir[--dirlen] = '\0';
178 if (dirlen <= 0)
179 return (-1);
181 status = chdir (dir);
182 free (dir);
184 if (status != 0)
185 {
186 if (errno == ENOENT)
187 {
188 if (mkdir (orig_dir, 0755) == -1)
189 {
190 char errbuf[1024];
191 ERROR ("change_basedir: mkdir (%s): %s", orig_dir,
192 sstrerror (errno, errbuf,
193 sizeof (errbuf)));
194 return (-1);
195 }
196 else if (chdir (orig_dir) == -1)
197 {
198 char errbuf[1024];
199 ERROR ("chdir (%s): %s", orig_dir,
200 sstrerror (errno, errbuf,
201 sizeof (errbuf)));
202 return (-1);
203 }
204 }
205 else
206 {
207 char errbuf[1024];
208 ERROR ("chdir (%s): %s", orig_dir,
209 sstrerror (errno, errbuf,
210 sizeof (errbuf)));
211 return (-1);
212 }
213 }
215 return (0);
216 } /* static int change_basedir (char *dir) */
218 #if HAVE_LIBKSTAT
219 static void update_kstat (void)
220 {
221 if (kc == NULL)
222 {
223 if ((kc = kstat_open ()) == NULL)
224 ERROR ("Unable to open kstat control structure");
225 }
226 else
227 {
228 kid_t kid;
229 kid = kstat_chain_update (kc);
230 if (kid > 0)
231 {
232 INFO ("kstat chain has been updated");
233 plugin_init_all ();
234 }
235 else if (kid < 0)
236 ERROR ("kstat chain update failed");
237 /* else: everything works as expected */
238 }
240 return;
241 } /* static void update_kstat (void) */
242 #endif /* HAVE_LIBKSTAT */
244 /* TODO
245 * Remove all settings but `-f' and `-C'
246 */
247 static void exit_usage (int status)
248 {
249 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
251 "Available options:\n"
252 " General:\n"
253 " -C <file> Configuration file.\n"
254 " Default: "CONFIGFILE"\n"
255 " -t Test config and exit.\n"
256 " -P <file> PID-file.\n"
257 " Default: "PIDFILE"\n"
258 #if COLLECT_DAEMON
259 " -f Don't fork to the background.\n"
260 #endif
261 " -h Display help (this message)\n"
262 "\nBuiltin defaults:\n"
263 " Config-File "CONFIGFILE"\n"
264 " PID-File "PIDFILE"\n"
265 " Data-Directory "PKGLOCALSTATEDIR"\n"
266 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
267 "by Florian octo Forster <octo@verplant.org>\n"
268 "for contributions see `AUTHORS'\n");
269 exit (status);
270 } /* static void exit_usage (int status) */
272 static int do_init (void)
273 {
274 #if HAVE_LIBKSTAT
275 kc = NULL;
276 update_kstat ();
277 #endif
279 #if HAVE_LIBSTATGRAB
280 if (sg_init ())
281 {
282 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
283 return (-1);
284 }
286 if (sg_drop_privileges ())
287 {
288 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
289 return (-1);
290 }
291 #endif
293 plugin_init_all ();
295 return (0);
296 } /* int do_init () */
299 static int do_loop (void)
300 {
301 struct timeval tv_now;
302 struct timeval tv_next;
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_sub_timespec (&tv_next, &tv_now, &ts_wait) != 0)
334 {
335 WARNING ("Not sleeping because "
336 "`timeval_sub_timespec' returned "
337 "non-zero!");
338 continue;
339 }
341 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
342 {
343 if (errno != EINTR)
344 {
345 char errbuf[1024];
346 ERROR ("nanosleep failed: %s",
347 sstrerror (errno, errbuf,
348 sizeof (errbuf)));
349 return (-1);
350 }
351 }
352 } /* while (loop == 0) */
354 DEBUG ("return (0);");
355 return (0);
356 } /* int do_loop */
358 static int do_shutdown (void)
359 {
360 plugin_shutdown_all ();
361 return (0);
362 } /* int do_shutdown */
364 #if COLLECT_DAEMON
365 static int pidfile_create (void)
366 {
367 FILE *fh;
368 const char *file = global_option_get ("PIDFile");
370 if ((fh = fopen (file, "w")) == NULL)
371 {
372 char errbuf[1024];
373 ERROR ("fopen (%s): %s", file,
374 sstrerror (errno, errbuf, sizeof (errbuf)));
375 return (1);
376 }
378 fprintf (fh, "%i\n", (int) getpid ());
379 fclose(fh);
381 return (0);
382 } /* static int pidfile_create (const char *file) */
384 static int pidfile_remove (void)
385 {
386 const char *file = global_option_get ("PIDFile");
388 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
389 return (unlink (file));
390 } /* static int pidfile_remove (const char *file) */
391 #endif /* COLLECT_DAEMON */
393 int main (int argc, char **argv)
394 {
395 struct sigaction sig_int_action;
396 struct sigaction sig_term_action;
397 struct sigaction sig_usr1_action;
398 struct sigaction sig_pipe_action;
399 char *configfile = CONFIGFILE;
400 int test_config = 0;
401 const char *basedir;
402 #if COLLECT_DAEMON
403 struct sigaction sig_chld_action;
404 pid_t pid;
405 int daemonize = 1;
406 #endif
408 /* read options */
409 while (1)
410 {
411 int c;
413 c = getopt (argc, argv, "htC:"
414 #if COLLECT_DAEMON
415 "fP:"
416 #endif
417 );
419 if (c == -1)
420 break;
422 switch (c)
423 {
424 case 'C':
425 configfile = optarg;
426 break;
427 case 't':
428 test_config = 1;
429 break;
430 #if COLLECT_DAEMON
431 case 'P':
432 global_option_set ("PIDFile", optarg);
433 break;
434 case 'f':
435 daemonize = 0;
436 break;
437 #endif /* COLLECT_DAEMON */
438 case 'h':
439 exit_usage (0);
440 break;
441 default:
442 exit_usage (1);
443 } /* switch (c) */
444 } /* while (1) */
446 if (optind < argc)
447 exit_usage (1);
449 /*
450 * Read options from the config file, the environment and the command
451 * line (in that order, with later options overwriting previous ones in
452 * general).
453 * Also, this will automatically load modules.
454 */
455 if (cf_read (configfile))
456 {
457 fprintf (stderr, "Error: Reading the config file failed!\n"
458 "Read the syslog for details.\n");
459 return (1);
460 }
462 /*
463 * Change directory. We do this _after_ reading the config and loading
464 * modules to relative paths work as expected.
465 */
466 if ((basedir = global_option_get ("BaseDir")) == NULL)
467 {
468 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
469 return (1);
470 }
471 else if (change_basedir (basedir))
472 {
473 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
474 return (1);
475 }
477 /*
478 * Set global variables or, if that failes, exit. We cannot run with
479 * them being uninitialized. If nothing is configured, then defaults
480 * are being used. So this means that the user has actually done
481 * something wrong.
482 */
483 if (init_global_variables () != 0)
484 return (1);
486 if (test_config)
487 return (0);
489 #if COLLECT_DAEMON
490 /*
491 * fork off child
492 */
493 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
494 sig_chld_action.sa_handler = SIG_IGN;
495 sigaction (SIGCHLD, &sig_chld_action, NULL);
497 if (daemonize)
498 {
499 if ((pid = fork ()) == -1)
500 {
501 /* error */
502 char errbuf[1024];
503 fprintf (stderr, "fork: %s",
504 sstrerror (errno, errbuf,
505 sizeof (errbuf)));
506 return (1);
507 }
508 else if (pid != 0)
509 {
510 /* parent */
511 /* printf ("Running (PID %i)\n", pid); */
512 return (0);
513 }
515 /* Detach from session */
516 setsid ();
518 /* Write pidfile */
519 if (pidfile_create ())
520 exit (2);
522 /* close standard descriptors */
523 close (2);
524 close (1);
525 close (0);
527 if (open ("/dev/null", O_RDWR) != 0)
528 {
529 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
530 return (1);
531 }
532 if (dup (0) != 1)
533 {
534 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
535 return (1);
536 }
537 if (dup (0) != 2)
538 {
539 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
540 return (1);
541 }
542 } /* if (daemonize) */
543 #endif /* COLLECT_DAEMON */
545 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
546 sig_pipe_action.sa_handler = SIG_IGN;
547 sigaction (SIGPIPE, &sig_pipe_action, NULL);
549 /*
550 * install signal handlers
551 */
552 memset (&sig_int_action, '\0', sizeof (sig_int_action));
553 sig_int_action.sa_handler = sig_int_handler;
554 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
555 char errbuf[1024];
556 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
557 sstrerror (errno, errbuf, sizeof (errbuf)));
558 return (1);
559 }
561 memset (&sig_term_action, '\0', sizeof (sig_term_action));
562 sig_term_action.sa_handler = sig_term_handler;
563 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
564 char errbuf[1024];
565 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
566 sstrerror (errno, errbuf, sizeof (errbuf)));
567 return (1);
568 }
570 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
571 sig_usr1_action.sa_handler = sig_usr1_handler;
572 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
573 char errbuf[1024];
574 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
575 sstrerror (errno, errbuf, sizeof (errbuf)));
576 return (1);
577 }
579 /*
580 * run the actual loops
581 */
582 do_init ();
583 do_loop ();
585 /* close syslog */
586 INFO ("Exiting normally");
588 do_shutdown ();
590 #if COLLECT_DAEMON
591 if (daemonize)
592 pidfile_remove ();
593 #endif /* COLLECT_DAEMON */
595 return (0);
596 } /* int main */