2d161aad6062815d4bdf220a7f30c02319e33075
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 "plugin.h"
31 #include "configfile.h"
33 /*
34 * Global variables
35 */
36 char hostname_g[DATA_MAX_NAME_LEN];
37 int interval_g;
38 #if HAVE_LIBKSTAT
39 kstat_ctl_t *kc;
40 #endif /* HAVE_LIBKSTAT */
42 static int loop = 0;
44 static void sigIntHandler (int signal)
45 {
46 loop++;
47 }
49 static void sigTermHandler (int signal)
50 {
51 loop++;
52 }
54 static int init_hostname (void)
55 {
56 const char *str;
58 struct addrinfo ai_hints;
59 struct addrinfo *ai_list;
60 struct addrinfo *ai_ptr;
61 int status;
63 str = global_option_get ("Hostname");
64 if (str != NULL)
65 {
66 strncpy (hostname_g, str, sizeof (hostname_g));
67 hostname_g[sizeof (hostname_g) - 1] = '\0';
68 return (0);
69 }
71 if (gethostname (hostname_g, sizeof (hostname_g)) != 0)
72 {
73 fprintf (stderr, "`gethostname' failed and no "
74 "hostname was configured.\n");
75 return (-1);
76 }
78 str = global_option_get ("FQDNLookup");
79 if ((strcasecmp ("false", str) == 0)
80 || (strcasecmp ("no", str) == 0)
81 || (strcasecmp ("off", str) == 0))
82 return (0);
84 memset (&ai_hints, '\0', sizeof (ai_hints));
85 ai_hints.ai_flags = AI_CANONNAME;
87 status = getaddrinfo (hostname_g, NULL, &ai_hints, &ai_list);
88 if (status != 0)
89 {
90 ERROR ("getaddrinfo failed.");
91 return (-1);
92 }
94 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
95 {
96 if (ai_ptr->ai_canonname == NULL)
97 continue;
99 strncpy (hostname_g, ai_ptr->ai_canonname, sizeof (hostname_g));
100 hostname_g[sizeof (hostname_g) - 1] = '\0';
101 break;
102 }
104 freeaddrinfo (ai_list);
105 return (0);
106 } /* int init_hostname */
108 static int init_global_variables (void)
109 {
110 const char *str;
112 str = global_option_get ("Interval");
113 if (str == NULL)
114 str = "10";
115 interval_g = atoi (str);
116 if (interval_g <= 0)
117 {
118 fprintf (stderr, "Cannot set the interval to a correct value.\n"
119 "Please check your settings.\n");
120 return (-1);
121 }
122 DEBUG ("interval_g = %i;", interval_g);
124 if (init_hostname () != 0)
125 return (-1);
126 DEBUG ("hostname_g = %s;", hostname_g);
128 return (0);
129 } /* int init_global_variables */
131 static int change_basedir (const char *orig_dir)
132 {
133 char *dir = strdup (orig_dir);
134 int dirlen;
135 int status;
137 if (dir == NULL)
138 {
139 char errbuf[1024];
140 ERROR ("strdup failed: %s",
141 sstrerror (errno, errbuf, sizeof (errbuf)));
142 return (-1);
143 }
145 dirlen = strlen (dir);
146 while ((dirlen > 0) && (dir[dirlen - 1] == '/'))
147 dir[--dirlen] = '\0';
149 if (dirlen <= 0)
150 return (-1);
152 status = chdir (dir);
153 free (dir);
155 if (status != 0)
156 {
157 if (errno == ENOENT)
158 {
159 if (mkdir (orig_dir, 0755) == -1)
160 {
161 char errbuf[1024];
162 ERROR ("change_basedir: mkdir (%s): %s", orig_dir,
163 sstrerror (errno, errbuf,
164 sizeof (errbuf)));
165 return (-1);
166 }
167 else if (chdir (orig_dir) == -1)
168 {
169 char errbuf[1024];
170 ERROR ("chdir (%s): %s", orig_dir,
171 sstrerror (errno, errbuf,
172 sizeof (errbuf)));
173 return (-1);
174 }
175 }
176 else
177 {
178 char errbuf[1024];
179 ERROR ("chdir (%s): %s", orig_dir,
180 sstrerror (errno, errbuf,
181 sizeof (errbuf)));
182 return (-1);
183 }
184 }
186 return (0);
187 } /* static int change_basedir (char *dir) */
189 #if HAVE_LIBKSTAT
190 static void update_kstat (void)
191 {
192 if (kc == NULL)
193 {
194 if ((kc = kstat_open ()) == NULL)
195 ERROR ("Unable to open kstat control structure");
196 }
197 else
198 {
199 kid_t kid;
200 kid = kstat_chain_update (kc);
201 if (kid > 0)
202 {
203 INFO ("kstat chain has been updated");
204 plugin_init_all ();
205 }
206 else if (kid < 0)
207 ERROR ("kstat chain update failed");
208 /* else: everything works as expected */
209 }
211 return;
212 } /* static void update_kstat (void) */
213 #endif /* HAVE_LIBKSTAT */
215 /* TODO
216 * Remove all settings but `-f' and `-C'
217 */
218 static void exit_usage (void)
219 {
220 printf ("Usage: "PACKAGE" [OPTIONS]\n\n"
222 "Available options:\n"
223 " General:\n"
224 " -C <file> Configuration file.\n"
225 " Default: "CONFIGFILE"\n"
226 " -P <file> PID-file.\n"
227 " Default: "PIDFILE"\n"
228 #if COLLECT_DAEMON
229 " -f Don't fork to the background.\n"
230 #endif
231 "\nBuiltin defaults:\n"
232 " Config-File "CONFIGFILE"\n"
233 " PID-File "PIDFILE"\n"
234 " Data-Directory "PKGLOCALSTATEDIR"\n"
235 "\n"PACKAGE" "VERSION", http://collectd.org/\n"
236 "by Florian octo Forster <octo@verplant.org>\n"
237 "for contributions see `AUTHORS'\n");
238 exit (0);
239 } /* static void exit_usage (char *name) */
241 static int do_init (void)
242 {
243 #if HAVE_LIBKSTAT
244 kc = NULL;
245 update_kstat ();
246 #endif
248 #if HAVE_LIBSTATGRAB
249 if (sg_init ())
250 {
251 ERROR ("sg_init: %s", sg_str_error (sg_get_error ()));
252 return (-1);
253 }
255 if (sg_drop_privileges ())
256 {
257 ERROR ("sg_drop_privileges: %s", sg_str_error (sg_get_error ()));
258 return (-1);
259 }
260 #endif
262 plugin_init_all ();
264 return (0);
265 } /* int do_init () */
268 static int do_loop (void)
269 {
270 struct timeval tv_now;
271 struct timeval tv_next;
272 struct timespec ts_wait;
274 while (loop == 0)
275 {
276 if (gettimeofday (&tv_next, NULL) < 0)
277 {
278 char errbuf[1024];
279 ERROR ("gettimeofday failed: %s",
280 sstrerror (errno, errbuf,
281 sizeof (errbuf)));
282 return (-1);
283 }
284 tv_next.tv_sec += interval_g;
286 #if HAVE_LIBKSTAT
287 update_kstat ();
288 #endif
290 /* Issue all plugins */
291 plugin_read_all ();
293 if (gettimeofday (&tv_now, NULL) < 0)
294 {
295 char errbuf[1024];
296 ERROR ("gettimeofday failed: %s",
297 sstrerror (errno, errbuf,
298 sizeof (errbuf)));
299 return (-1);
300 }
302 if (timeval_sub_timespec (&tv_next, &tv_now, &ts_wait) != 0)
303 {
304 WARNING ("Not sleeping because "
305 "`timeval_sub_timespec' returned "
306 "non-zero!");
307 continue;
308 }
310 while ((loop == 0) && (nanosleep (&ts_wait, &ts_wait) == -1))
311 {
312 if (errno != EINTR)
313 {
314 char errbuf[1024];
315 ERROR ("nanosleep failed: %s",
316 sstrerror (errno, errbuf,
317 sizeof (errbuf)));
318 return (-1);
319 }
320 }
321 } /* while (loop == 0) */
323 DEBUG ("return (0);");
324 return (0);
325 } /* int do_loop */
327 static int do_shutdown (void)
328 {
329 plugin_shutdown_all ();
330 return (0);
331 } /* int do_shutdown */
333 #if COLLECT_DAEMON
334 static int pidfile_create (void)
335 {
336 FILE *fh;
337 const char *file = global_option_get ("PIDFile");
339 if ((fh = fopen (file, "w")) == NULL)
340 {
341 char errbuf[1024];
342 ERROR ("fopen (%s): %s", file,
343 sstrerror (errno, errbuf, sizeof (errbuf)));
344 return (1);
345 }
347 fprintf (fh, "%i\n", (int) getpid ());
348 fclose(fh);
350 return (0);
351 } /* static int pidfile_create (const char *file) */
353 static int pidfile_remove (void)
354 {
355 const char *file = global_option_get ("PIDFile");
357 DEBUG ("unlink (%s)", (file != NULL) ? file : "<null>");
358 return (unlink (file));
359 } /* static int pidfile_remove (const char *file) */
360 #endif /* COLLECT_DAEMON */
362 int main (int argc, char **argv)
363 {
364 struct sigaction sigIntAction;
365 struct sigaction sigTermAction;
366 char *configfile = CONFIGFILE;
367 int test_config = 0;
368 const char *basedir;
369 #if COLLECT_DAEMON
370 struct sigaction sigChldAction;
371 pid_t pid;
372 int daemonize = 1;
373 #endif
375 /* read options */
376 while (1)
377 {
378 int c;
380 c = getopt (argc, argv, "htC:"
381 #if COLLECT_DAEMON
382 "fP:"
383 #endif
384 );
386 if (c == -1)
387 break;
389 switch (c)
390 {
391 case 'C':
392 configfile = optarg;
393 break;
394 case 't':
395 test_config = 1;
396 break;
397 #if COLLECT_DAEMON
398 case 'P':
399 global_option_set ("PIDFile", optarg);
400 break;
401 case 'f':
402 daemonize = 0;
403 break;
404 #endif /* COLLECT_DAEMON */
405 case 'h':
406 default:
407 exit_usage ();
408 } /* switch (c) */
409 } /* while (1) */
411 /*
412 * Read options from the config file, the environment and the command
413 * line (in that order, with later options overwriting previous ones in
414 * general).
415 * Also, this will automatically load modules.
416 */
417 if (cf_read (configfile))
418 {
419 fprintf (stderr, "Error: Reading the config file failed!\n"
420 "Read the syslog for details.\n");
421 return (1);
422 }
424 /*
425 * Change directory. We do this _after_ reading the config and loading
426 * modules to relative paths work as expected.
427 */
428 if ((basedir = global_option_get ("BaseDir")) == NULL)
429 {
430 fprintf (stderr, "Don't have a basedir to use. This should not happen. Ever.");
431 return (1);
432 }
433 else if (change_basedir (basedir))
434 {
435 fprintf (stderr, "Error: Unable to change to directory `%s'.\n", basedir);
436 return (1);
437 }
439 /*
440 * Set global variables or, if that failes, exit. We cannot run with
441 * them being uninitialized. If nothing is configured, then defaults
442 * are being used. So this means that the user has actually done
443 * something wrong.
444 */
445 if (init_global_variables () != 0)
446 return (1);
448 if (test_config)
449 return (0);
451 #if COLLECT_DAEMON
452 /*
453 * fork off child
454 */
455 memset (&sigChldAction, '\0', sizeof (sigChldAction));
456 sigChldAction.sa_handler = SIG_IGN;
457 sigaction (SIGCHLD, &sigChldAction, NULL);
459 if (daemonize)
460 {
461 if ((pid = fork ()) == -1)
462 {
463 /* error */
464 char errbuf[1024];
465 fprintf (stderr, "fork: %s",
466 sstrerror (errno, errbuf,
467 sizeof (errbuf)));
468 return (1);
469 }
470 else if (pid != 0)
471 {
472 /* parent */
473 /* printf ("Running (PID %i)\n", pid); */
474 return (0);
475 }
477 /* Detach from session */
478 setsid ();
480 /* Write pidfile */
481 if (pidfile_create ())
482 exit (2);
484 /* close standard descriptors */
485 close (2);
486 close (1);
487 close (0);
489 if (open ("/dev/null", O_RDWR) != 0)
490 {
491 ERROR ("Error: Could not connect `STDIN' to `/dev/null'");
492 return (1);
493 }
494 if (dup (0) != 1)
495 {
496 ERROR ("Error: Could not connect `STDOUT' to `/dev/null'");
497 return (1);
498 }
499 if (dup (0) != 2)
500 {
501 ERROR ("Error: Could not connect `STDERR' to `/dev/null'");
502 return (1);
503 }
504 } /* if (daemonize) */
505 #endif /* COLLECT_DAEMON */
507 /*
508 * install signal handlers
509 */
510 memset (&sigIntAction, '\0', sizeof (sigIntAction));
511 sigIntAction.sa_handler = sigIntHandler;
512 sigaction (SIGINT, &sigIntAction, NULL);
514 memset (&sigTermAction, '\0', sizeof (sigTermAction));
515 sigTermAction.sa_handler = sigTermHandler;
516 sigaction (SIGTERM, &sigTermAction, NULL);
518 /*
519 * run the actual loops
520 */
521 do_init ();
522 do_loop ();
524 /* close syslog */
525 INFO ("Exiting normally");
527 do_shutdown ();
529 #if COLLECT_DAEMON
530 if (daemonize)
531 pidfile_remove ();
532 #endif /* COLLECT_DAEMON */
534 return (0);
535 } /* int main */