2044b49cf8689184a756305d7e02d60616f0694c
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 /*
36 * Global variables
37 */
38 char hostname_g[DATA_MAX_NAME_LEN];
39 int interval_g;
40 #if HAVE_LIBKSTAT
41 kstat_ctl_t *kc;
42 #endif /* HAVE_LIBKSTAT */
44 static int loop = 0;
46 static void *do_flush (void *arg)
47 {
48 INFO ("Flushing all data.");
49 plugin_flush_all (-1);
50 INFO ("Finished flushing all data.");
51 pthread_exit (NULL);
52 return NULL;
53 }
55 static void sig_int_handler (int signal)
56 {
57 loop++;
58 }
60 static void sig_term_handler (int signal)
61 {
62 loop++;
63 }
65 static void sig_usr1_handler (int signal)
66 {
67 pthread_t thread;
68 pthread_attr_t attr;
70 /* flushing the data might take a while,
71 * so it should be done asynchronously */
72 pthread_attr_init (&attr);
73 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
74 pthread_create (&thread, &attr, do_flush, NULL);
75 }
77 static int init_hostname (void)
78 {
79 const char *str;
81 struct addrinfo ai_hints;
82 struct addrinfo *ai_list;
83 struct addrinfo *ai_ptr;
84 int status;
86 str = global_option_get ("Hostname");
87 if (str != NULL)
88 {
89 sstrncpy (hostname_g, str, sizeof (hostname_g));
90 return (0);
91 }
93 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
94 {
95 fprintf (stderr, "`gethostname' failed and no "
96 "hostname was configured.\n");
97 return (-1);
98 }
100 str = global_option_get ("FQDNLookup");
101 if ((strcasecmp ("false", str) == 0)
102 || (strcasecmp ("no", str) == 0)
103 || (strcasecmp ("off", str) == 0))
104 return (0);
106 memset (&ai_hints, '\0', sizeof (ai_hints));
107 ai_hints.ai_flags = AI_CANONNAME;
109 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
110 if (status != 0)
111 {
112 ERROR ("Looking up \"%s\" failed. You have set the "
113 "\"FQDNLookup\" option, but I cannot resolve "
114 "my hostname to a fully qualified domain "
115 "name. Please fix you network "
116 "configuration.", hostname_g);
117 return (-1);
118 }
120 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
121 {
122 if (ai_ptr->ai_canonname == NULL)
123 continue;
125 sstrncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
126 break;
127 }
129 freeaddrinfo (ai_list);
130 return (0);
131 } /* int init_hostname */
133 static int init_global_variables (void)
134 {
135 const char *str;
137 str = global_option_get ("Interval");
138 if (str == NULL)
139 str = "10";
140 interval_g = atoi (str);
141 if (interval_g <= 0)
142 {
143 fprintf (stderr, "Cannot set the interval to a correct value.\n"
144 "Please check your settings.\n");
145 return (-1);
146 }
147 DEBUG ("interval_g = %i;", interval_g);
149 if (init_hostname () != 0)
150 return (-1);
151 DEBUG ("hostname_g = %s;", hostname_g);
153 return (0);
154 } /* int init_global_variables */
156 static int change_basedir (const char *orig_dir)
157 {
158 char *dir = strdup (orig_dir);
159 int dirlen;
160 int status;
162 if (dir == NULL)
163 {
164 char errbuf[1024];
165 ERROR ("strdup failed: %s",
166 sstrerror (errno, errbuf, sizeof (errbuf)));
167 return (-1);
168 }
170 dirlen = strlen (dir);
171 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
172 dir[--dirlen] = '\0';
174 if (dirlen <= 0)
175 return (-1);
177 status = chdir (dir);
178 free (dir);
180 if (status != 0)
181 {
182 if (errno == ENOENT)
183 {
184 if (mkdir (orig_dir, 0755) == -1)
185 {
186 char errbuf[1024];
187 ERROR ("change_basedir: mkdir (%s): %s", orig_dir,
188 sstrerror (errno, errbuf,
189 sizeof (errbuf)));
190 return (-1);
191 }
192 else if (chdir (orig_dir) == -1)
193 {
194 char errbuf[1024];
195 ERROR ("chdir (%s): %s", orig_dir,
196 sstrerror (errno, errbuf,
197 sizeof (errbuf)));
198 return (-1);
199 }
200 }
201 else
202 {
203 char errbuf[1024];
204 ERROR ("chdir (%s): %s", orig_dir,
205 sstrerror (errno, errbuf,
206 sizeof (errbuf)));
207 return (-1);
208 }
209 }
211 return (0);
212 } /* static int change_basedir (char *dir) */
214 #if HAVE_LIBKSTAT
215 static void update_kstat (void)
216 {
217 if (kc == NULL)
218 {
219 if ((kc = kstat_open ()) == NULL)
220 ERROR ("Unable to open kstat control structure");
221 }
222 else
223 {
224 kid_t kid;
225 kid = kstat_chain_update (kc);
226 if (kid > 0)
227 {
228 INFO ("kstat chain has been updated");
229 plugin_init_all ();
230 }
231 else if (kid < 0)
232 ERROR ("kstat chain update failed");
233 /* else: everything works as expected */
234 }
236 return;
237 } /* static void update_kstat (void) */
238 #endif /* HAVE_LIBKSTAT */
240 /* TODO
241 * Remove all settings but `-f' and `-C'
242 */
243 static void exit_usage (void)
244 {
245 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
247 "Available options:\n"
248 " General:\n"
249 " -C <file> Configuration file.\n"
250 " Default: "CONFIGFILE"\n"
251 " -t Test config and exit.\n"
252 " -P <file> PID-file.\n"
253 " Default: "PIDFILE"\n"
254 #if COLLECT_DAEMON
255 " -f Don't fork to the background.\n"
256 #endif
257 " -h Display help (this message)\n"
258 "\nBuiltin defaults:\n"
259 " Config-File "CONFIGFILE"\n"
260 " PID-File "PIDFILE"\n"
261 " Data-Directory "PKGLOCALSTATEDIR"\n"
262 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
263 "by Florian octo Forster <octo@verplant.org>\n"
264 "for contributions see `AUTHORS'\n");
265 exit (0);
266 } /* static void exit_usage (char *name) */
268 static int do_init (void)
269 {
270 #if HAVE_LIBKSTAT
271 kc = NULL;
272 update_kstat ();
273 #endif
275 #if HAVE_LIBSTATGRAB
276 if (sg_init ())
277 {
278 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
279 return (-1);
280 }
282 if (sg_drop_privileges ())
283 {
284 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
285 return (-1);
286 }
287 #endif
289 plugin_init_all ();
291 return (0);
292 } /* int do_init () */
295 static int do_loop (void)
296 {
297 struct timeval tv_now;
298 struct timeval tv_next;
299 struct timespec ts_wait;
301 while (loop == 0)
302 {
303 if (gettimeofday (&tv_next, NULL) < 0)
304 {
305 char errbuf[1024];
306 ERROR ("gettimeofday failed: %s",
307 sstrerror (errno, errbuf,
308 sizeof (errbuf)));
309 return (-1);
310 }
311 tv_next.tv_sec += interval_g;
313 #if HAVE_LIBKSTAT
314 update_kstat ();
315 #endif
317 /* Issue all plugins */
318 plugin_read_all ();
320 if (gettimeofday (&tv_now, NULL) < 0)
321 {
322 char errbuf[1024];
323 ERROR ("gettimeofday failed: %s",
324 sstrerror (errno, errbuf,
325 sizeof (errbuf)));
326 return (-1);
327 }
329 if (timeval_sub_timespec (&tv_next, &tv_now, &ts_wait) != 0)
330 {
331 WARNING ("Not sleeping because "
332 "`timeval_sub_timespec' returned "
333 "non-zero!");
334 continue;
335 }
337 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
338 {
339 if (errno != EINTR)
340 {
341 char errbuf[1024];
342 ERROR ("nanosleep failed: %s",
343 sstrerror (errno, errbuf,
344 sizeof (errbuf)));
345 return (-1);
346 }
347 }
348 } /* while (loop == 0) */
350 DEBUG ("return (0);");
351 return (0);
352 } /* int do_loop */
354 static int do_shutdown (void)
355 {
356 plugin_shutdown_all ();
357 return (0);
358 } /* int do_shutdown */
360 #if COLLECT_DAEMON
361 static int pidfile_create (void)
362 {
363 FILE *fh;
364 const char *file = global_option_get ("PIDFile");
366 if ((fh = fopen (file, "w")) == NULL)
367 {
368 char errbuf[1024];
369 ERROR ("fopen (%s): %s", file,
370 sstrerror (errno, errbuf, sizeof (errbuf)));
371 return (1);
372 }
374 fprintf (fh, "%i\n", (int) getpid ());
375 fclose(fh);
377 return (0);
378 } /* static int pidfile_create (const char *file) */
380 static int pidfile_remove (void)
381 {
382 const char *file = global_option_get ("PIDFile");
384 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
385 return (unlink (file));
386 } /* static int pidfile_remove (const char *file) */
387 #endif /* COLLECT_DAEMON */
389 int main (int argc, char **argv)
390 {
391 struct sigaction sig_int_action;
392 struct sigaction sig_term_action;
393 struct sigaction sig_usr1_action;
394 char *configfile = CONFIGFILE;
395 int test_config = 0;
396 const char *basedir;
397 #if COLLECT_DAEMON
398 struct sigaction sigChldAction;
399 pid_t pid;
400 int daemonize = 1;
401 #endif
403 /* read options */
404 while (1)
405 {
406 int c;
408 c = getopt (argc, argv, "htC:"
409 #if COLLECT_DAEMON
410 "fP:"
411 #endif
412 );
414 if (c == -1)
415 break;
417 switch (c)
418 {
419 case 'C':
420 configfile = optarg;
421 break;
422 case 't':
423 test_config = 1;
424 break;
425 #if COLLECT_DAEMON
426 case 'P':
427 global_option_set ("PIDFile", optarg);
428 break;
429 case 'f':
430 daemonize = 0;
431 break;
432 #endif /* COLLECT_DAEMON */
433 case 'h':
434 default:
435 exit_usage ();
436 } /* switch (c) */
437 } /* while (1) */
439 /*
440 * Read options from the config file, the environment and the command
441 * line (in that order, with later options overwriting previous ones in
442 * general).
443 * Also, this will automatically load modules.
444 */
445 if (cf_read (configfile))
446 {
447 fprintf (stderr, "Error: Reading the config file failed!\n"
448 "Read the syslog for details.\n");
449 return (1);
450 }
452 /*
453 * Change directory. We do this _after_ reading the config and loading
454 * modules to relative paths work as expected.
455 */
456 if ((basedir = global_option_get ("BaseDir")) == NULL)
457 {
458 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
459 return (1);
460 }
461 else if (change_basedir (basedir))
462 {
463 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
464 return (1);
465 }
467 /*
468 * Set global variables or, if that failes, exit. We cannot run with
469 * them being uninitialized. If nothing is configured, then defaults
470 * are being used. So this means that the user has actually done
471 * something wrong.
472 */
473 if (init_global_variables () != 0)
474 return (1);
476 if (test_config)
477 return (0);
479 #if COLLECT_DAEMON
480 /*
481 * fork off child
482 */
483 memset (&sigChldAction, '\0', sizeof (sigChldAction));
484 sigChldAction.sa_handler = SIG_IGN;
485 sigaction (SIGCHLD, &sigChldAction, NULL);
487 if (daemonize)
488 {
489 if ((pid = fork ()) == -1)
490 {
491 /* error */
492 char errbuf[1024];
493 fprintf (stderr, "fork: %s",
494 sstrerror (errno, errbuf,
495 sizeof (errbuf)));
496 return (1);
497 }
498 else if (pid != 0)
499 {
500 /* parent */
501 /* printf ("Running (PID %i)\n", pid); */
502 return (0);
503 }
505 /* Detach from session */
506 setsid ();
508 /* Write pidfile */
509 if (pidfile_create ())
510 exit (2);
512 /* close standard descriptors */
513 close (2);
514 close (1);
515 close (0);
517 if (open ("/dev/null", O_RDWR) != 0)
518 {
519 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
520 return (1);
521 }
522 if (dup (0) != 1)
523 {
524 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
525 return (1);
526 }
527 if (dup (0) != 2)
528 {
529 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
530 return (1);
531 }
532 } /* if (daemonize) */
533 #endif /* COLLECT_DAEMON */
535 /*
536 * install signal handlers
537 */
538 memset (&sig_int_action, '\0', sizeof (sig_int_action));
539 sig_int_action.sa_handler = sig_int_handler;
540 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
541 char errbuf[1024];
542 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
543 sstrerror (errno, errbuf, sizeof (errbuf)));
544 return (1);
545 }
547 memset (&sig_term_action, '\0', sizeof (sig_term_action));
548 sig_term_action.sa_handler = sig_term_handler;
549 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
550 char errbuf[1024];
551 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
552 sstrerror (errno, errbuf, sizeof (errbuf)));
553 return (1);
554 }
556 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
557 sig_usr1_action.sa_handler = sig_usr1_handler;
558 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
559 char errbuf[1024];
560 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
561 sstrerror (errno, errbuf, sizeof (errbuf)));
562 return (1);
563 }
565 /*
566 * run the actual loops
567 */
568 do_init ();
569 do_loop ();
571 /* close syslog */
572 INFO ("Exiting normally");
574 do_shutdown ();
576 #if COLLECT_DAEMON
577 if (daemonize)
578 pidfile_remove ();
579 #endif /* COLLECT_DAEMON */
581 return (0);
582 } /* int main */