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_all (-1);
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 strncpy (hostname_g, str, sizeof (hostname_g));
94 hostname_g[sizeof (hostname_g) - 1] = '\0';
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 ((strcasecmp ("false", str) == 0)
107 || (strcasecmp ("no", str) == 0)
108 || (strcasecmp ("off", str) == 0))
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 strncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
131 hostname_g[sizeof (hostname_g) - 1] = '\0';
132 break;
133 }
135 freeaddrinfo (ai_list);
136 return (0);
137 } /* int init_hostname */
139 static int init_global_variables (void)
140 {
141 const char *str;
143 str = global_option_get ("Interval");
144 if (str == NULL)
145 str = "10";
146 interval_g = atoi (str);
147 if (interval_g <= 0)
148 {
149 fprintf (stderr, "Cannot set the interval to a correct value.\n"
150 "Please check your settings.\n");
151 return (-1);
152 }
153 DEBUG ("interval_g = %i;", interval_g);
155 if (init_hostname () != 0)
156 return (-1);
157 DEBUG ("hostname_g = %s;", hostname_g);
159 return (0);
160 } /* int init_global_variables */
162 static int change_basedir (const char *orig_dir)
163 {
164 char *dir = strdup (orig_dir);
165 int dirlen;
166 int status;
168 if (dir == NULL)
169 {
170 char errbuf[1024];
171 ERROR ("strdup failed: %s",
172 sstrerror (errno, errbuf, sizeof (errbuf)));
173 return (-1);
174 }
176 dirlen = strlen (dir);
177 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
178 dir[--dirlen] = '\0';
180 if (dirlen <= 0)
181 return (-1);
183 status = chdir (dir);
184 free (dir);
186 if (status != 0)
187 {
188 if (errno == ENOENT)
189 {
190 if (mkdir (orig_dir, 0755) == -1)
191 {
192 char errbuf[1024];
193 ERROR ("change_basedir: mkdir (%s): %s", orig_dir,
194 sstrerror (errno, errbuf,
195 sizeof (errbuf)));
196 return (-1);
197 }
198 else if (chdir (orig_dir) == -1)
199 {
200 char errbuf[1024];
201 ERROR ("chdir (%s): %s", orig_dir,
202 sstrerror (errno, errbuf,
203 sizeof (errbuf)));
204 return (-1);
205 }
206 }
207 else
208 {
209 char errbuf[1024];
210 ERROR ("chdir (%s): %s", orig_dir,
211 sstrerror (errno, errbuf,
212 sizeof (errbuf)));
213 return (-1);
214 }
215 }
217 return (0);
218 } /* static int change_basedir (char *dir) */
220 #if HAVE_LIBKSTAT
221 static void update_kstat (void)
222 {
223 if (kc == NULL)
224 {
225 if ((kc = kstat_open ()) == NULL)
226 ERROR ("Unable to open kstat control structure");
227 }
228 else
229 {
230 kid_t kid;
231 kid = kstat_chain_update (kc);
232 if (kid > 0)
233 {
234 INFO ("kstat chain has been updated");
235 plugin_init_all ();
236 }
237 else if (kid < 0)
238 ERROR ("kstat chain update failed");
239 /* else: everything works as expected */
240 }
242 return;
243 } /* static void update_kstat (void) */
244 #endif /* HAVE_LIBKSTAT */
246 /* TODO
247 * Remove all settings but `-f' and `-C'
248 */
249 static void exit_usage (void)
250 {
251 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
253 "Available options:\n"
254 " General:\n"
255 " -C <file> Configuration file.\n"
256 " Default: "CONFIGFILE"\n"
257 " -t Test config and exit.\n"
258 " -P <file> PID-file.\n"
259 " Default: "PIDFILE"\n"
260 #if COLLECT_DAEMON
261 " -f Don't fork to the background.\n"
262 #endif
263 " -h Display help (this message)\n"
264 "\nBuiltin defaults:\n"
265 " Config-File "CONFIGFILE"\n"
266 " PID-File "PIDFILE"\n"
267 " Data-Directory "PKGLOCALSTATEDIR"\n"
268 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
269 "by Florian octo Forster <octo@verplant.org>\n"
270 "for contributions see `AUTHORS'\n");
271 exit (0);
272 } /* static void exit_usage (char *name) */
274 static int do_init (void)
275 {
276 #if HAVE_LIBKSTAT
277 kc = NULL;
278 update_kstat ();
279 #endif
281 #if HAVE_LIBSTATGRAB
282 if (sg_init ())
283 {
284 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
285 return (-1);
286 }
288 if (sg_drop_privileges ())
289 {
290 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
291 return (-1);
292 }
293 #endif
295 plugin_init_all ();
297 return (0);
298 } /* int do_init () */
301 static int do_loop (void)
302 {
303 struct timeval tv_now;
304 struct timeval tv_next;
305 struct timespec ts_wait;
307 while (loop == 0)
308 {
309 if (gettimeofday (&tv_next, NULL) < 0)
310 {
311 char errbuf[1024];
312 ERROR ("gettimeofday failed: %s",
313 sstrerror (errno, errbuf,
314 sizeof (errbuf)));
315 return (-1);
316 }
317 tv_next.tv_sec += interval_g;
319 #if HAVE_LIBKSTAT
320 update_kstat ();
321 #endif
323 /* Issue all plugins */
324 plugin_read_all ();
326 if (gettimeofday (&tv_now, NULL) < 0)
327 {
328 char errbuf[1024];
329 ERROR ("gettimeofday failed: %s",
330 sstrerror (errno, errbuf,
331 sizeof (errbuf)));
332 return (-1);
333 }
335 if (timeval_sub_timespec (&tv_next, &tv_now, &ts_wait) != 0)
336 {
337 WARNING ("Not sleeping because "
338 "`timeval_sub_timespec' returned "
339 "non-zero!");
340 continue;
341 }
343 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
344 {
345 if (errno != EINTR)
346 {
347 char errbuf[1024];
348 ERROR ("nanosleep failed: %s",
349 sstrerror (errno, errbuf,
350 sizeof (errbuf)));
351 return (-1);
352 }
353 }
354 } /* while (loop == 0) */
356 DEBUG ("return (0);");
357 return (0);
358 } /* int do_loop */
360 static int do_shutdown (void)
361 {
362 plugin_shutdown_all ();
363 return (0);
364 } /* int do_shutdown */
366 #if COLLECT_DAEMON
367 static int pidfile_create (void)
368 {
369 FILE *fh;
370 const char *file = global_option_get ("PIDFile");
372 if ((fh = fopen (file, "w")) == NULL)
373 {
374 char errbuf[1024];
375 ERROR ("fopen (%s): %s", file,
376 sstrerror (errno, errbuf, sizeof (errbuf)));
377 return (1);
378 }
380 fprintf (fh, "%i\n", (int) getpid ());
381 fclose(fh);
383 return (0);
384 } /* static int pidfile_create (const char *file) */
386 static int pidfile_remove (void)
387 {
388 const char *file = global_option_get ("PIDFile");
390 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
391 return (unlink (file));
392 } /* static int pidfile_remove (const char *file) */
393 #endif /* COLLECT_DAEMON */
395 int main (int argc, char **argv)
396 {
397 struct sigaction sig_int_action;
398 struct sigaction sig_term_action;
399 struct sigaction sig_usr1_action;
400 struct sigaction sig_pipe_action;
401 char *configfile = CONFIGFILE;
402 int test_config = 0;
403 const char *basedir;
404 #if COLLECT_DAEMON
405 struct sigaction sig_chld_action;
406 pid_t pid;
407 int daemonize = 1;
408 #endif
410 /* read options */
411 while (1)
412 {
413 int c;
415 c = getopt (argc, argv, "htC:"
416 #if COLLECT_DAEMON
417 "fP:"
418 #endif
419 );
421 if (c == -1)
422 break;
424 switch (c)
425 {
426 case 'C':
427 configfile = optarg;
428 break;
429 case 't':
430 test_config = 1;
431 break;
432 #if COLLECT_DAEMON
433 case 'P':
434 global_option_set ("PIDFile", optarg);
435 break;
436 case 'f':
437 daemonize = 0;
438 break;
439 #endif /* COLLECT_DAEMON */
440 case 'h':
441 default:
442 exit_usage ();
443 } /* switch (c) */
444 } /* while (1) */
446 /*
447 * Read options from the config file, the environment and the command
448 * line (in that order, with later options overwriting previous ones in
449 * general).
450 * Also, this will automatically load modules.
451 */
452 if (cf_read (configfile))
453 {
454 fprintf (stderr, "Error: Reading the config file failed!\n"
455 "Read the syslog for details.\n");
456 return (1);
457 }
459 /*
460 * Change directory. We do this _after_ reading the config and loading
461 * modules to relative paths work as expected.
462 */
463 if ((basedir = global_option_get ("BaseDir")) == NULL)
464 {
465 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
466 return (1);
467 }
468 else if (change_basedir (basedir))
469 {
470 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
471 return (1);
472 }
474 /*
475 * Set global variables or, if that failes, exit. We cannot run with
476 * them being uninitialized. If nothing is configured, then defaults
477 * are being used. So this means that the user has actually done
478 * something wrong.
479 */
480 if (init_global_variables () != 0)
481 return (1);
483 if (test_config)
484 return (0);
486 #if COLLECT_DAEMON
487 /*
488 * fork off child
489 */
490 memset (&sig_chld_action, '\0', sizeof (sig_chld_action));
491 sig_chld_action.sa_handler = SIG_IGN;
492 sigaction (SIGCHLD, &sig_chld_action, NULL);
494 if (daemonize)
495 {
496 if ((pid = fork ()) == -1)
497 {
498 /* error */
499 char errbuf[1024];
500 fprintf (stderr, "fork: %s",
501 sstrerror (errno, errbuf,
502 sizeof (errbuf)));
503 return (1);
504 }
505 else if (pid != 0)
506 {
507 /* parent */
508 /* printf ("Running (PID %i)\n", pid); */
509 return (0);
510 }
512 /* Detach from session */
513 setsid ();
515 /* Write pidfile */
516 if (pidfile_create ())
517 exit (2);
519 /* close standard descriptors */
520 close (2);
521 close (1);
522 close (0);
524 if (open ("/dev/null", O_RDWR) != 0)
525 {
526 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
527 return (1);
528 }
529 if (dup (0) != 1)
530 {
531 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
532 return (1);
533 }
534 if (dup (0) != 2)
535 {
536 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
537 return (1);
538 }
539 } /* if (daemonize) */
540 #endif /* COLLECT_DAEMON */
542 memset (&sig_pipe_action, '\0', sizeof (sig_pipe_action));
543 sig_pipe_action.sa_handler = SIG_IGN;
544 sigaction (SIGPIPE, &sig_pipe_action, NULL);
546 /*
547 * install signal handlers
548 */
549 memset (&sig_int_action, '\0', sizeof (sig_int_action));
550 sig_int_action.sa_handler = sig_int_handler;
551 if (0 != sigaction (SIGINT, &sig_int_action, NULL)) {
552 char errbuf[1024];
553 ERROR ("Error: Failed to install a signal handler for signal INT: %s",
554 sstrerror (errno, errbuf, sizeof (errbuf)));
555 return (1);
556 }
558 memset (&sig_term_action, '\0', sizeof (sig_term_action));
559 sig_term_action.sa_handler = sig_term_handler;
560 if (0 != sigaction (SIGTERM, &sig_term_action, NULL)) {
561 char errbuf[1024];
562 ERROR ("Error: Failed to install a signal handler for signal TERM: %s",
563 sstrerror (errno, errbuf, sizeof (errbuf)));
564 return (1);
565 }
567 memset (&sig_usr1_action, '\0', sizeof (sig_usr1_action));
568 sig_usr1_action.sa_handler = sig_usr1_handler;
569 if (0 != sigaction (SIGUSR1, &sig_usr1_action, NULL)) {
570 char errbuf[1024];
571 ERROR ("Error: Failed to install a signal handler for signal USR1: %s",
572 sstrerror (errno, errbuf, sizeof (errbuf)));
573 return (1);
574 }
576 /*
577 * run the actual loops
578 */
579 do_init ();
580 do_loop ();
582 /* close syslog */
583 INFO ("Exiting normally");
585 do_shutdown ();
587 #if COLLECT_DAEMON
588 if (daemonize)
589 pidfile_remove ();
590 #endif /* COLLECT_DAEMON */
592 return (0);
593 } /* int main */