1 /**
2 * collectd - src/ping.c
3 * Copyright (C) 2005-2009 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 **/
22 #include "collectd.h"
23 #include "common.h"
24 #include "plugin.h"
25 #include "configfile.h"
27 #include <pthread.h>
28 #include <netinet/in.h>
29 #if HAVE_NETDB_H
30 # include <netdb.h> /* NI_MAXHOST */
31 #endif
33 #include <oping.h>
35 #ifndef NI_MAXHOST
36 # define NI_MAXHOST 1025
37 #endif
39 #if defined(OPING_VERSION) && (OPING_VERSION >= 1003000)
40 # define HAVE_OPING_1_3
41 #endif
43 /*
44 * Private data types
45 */
46 struct hostlist_s
47 {
48 char *host;
50 uint32_t pkg_sent;
51 uint32_t pkg_recv;
52 uint32_t pkg_missed;
54 double latency_total;
55 double latency_squared;
57 struct hostlist_s *next;
58 };
59 typedef struct hostlist_s hostlist_t;
61 /*
62 * Private variables
63 */
64 static hostlist_t *hostlist_head = NULL;
66 static char *ping_source = NULL;
67 #ifdef HAVE_OPING_1_3
68 static char *ping_device = NULL;
69 #endif
70 static int ping_ttl = PING_DEF_TTL;
71 static double ping_interval = 1.0;
72 static double ping_timeout = 0.9;
73 static int ping_max_missed = -1;
75 static int ping_thread_loop = 0;
76 static int ping_thread_error = 0;
77 static pthread_t ping_thread_id;
78 static pthread_mutex_t ping_lock = PTHREAD_MUTEX_INITIALIZER;
79 static pthread_cond_t ping_cond = PTHREAD_COND_INITIALIZER;
81 static const char *config_keys[] =
82 {
83 "Host",
84 "SourceAddress",
85 #ifdef HAVE_OPING_1_3
86 "Device",
87 #endif
88 "TTL",
89 "Interval",
90 "Timeout",
91 "MaxMissed"
92 };
93 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
95 /*
96 * Private functions
97 */
98 /* Assure that `ts->tv_nsec' is in the range 0 .. 999999999 */
99 static void time_normalize (struct timespec *ts) /* {{{ */
100 {
101 while (ts->tv_nsec < 0)
102 {
103 if (ts->tv_sec == 0)
104 {
105 ts->tv_nsec = 0;
106 return;
107 }
109 ts->tv_sec -= 1;
110 ts->tv_nsec += 1000000000;
111 }
113 while (ts->tv_nsec >= 1000000000)
114 {
115 ts->tv_sec += 1;
116 ts->tv_nsec -= 1000000000;
117 }
118 } /* }}} void time_normalize */
120 /* Add `ts_int' to `tv_begin' and store the result in `ts_dest'. If the result
121 * is larger than `tv_end', copy `tv_end' to `ts_dest' instead. */
122 static void time_calc (struct timespec *ts_dest, /* {{{ */
123 const struct timespec *ts_int,
124 const struct timeval *tv_begin,
125 const struct timeval *tv_end)
126 {
127 ts_dest->tv_sec = tv_begin->tv_sec + ts_int->tv_sec;
128 ts_dest->tv_nsec = (tv_begin->tv_usec * 1000) + ts_int->tv_nsec;
129 time_normalize (ts_dest);
131 /* Assure that `(begin + interval) > end'.
132 * This may seem overly complicated, but `tv_sec' is of type `time_t'
133 * which may be `unsigned. *sigh* */
134 if ((tv_end->tv_sec > ts_dest->tv_sec)
135 || ((tv_end->tv_sec == ts_dest->tv_sec)
136 && ((tv_end->tv_usec * 1000) > ts_dest->tv_nsec)))
137 {
138 ts_dest->tv_sec = tv_end->tv_sec;
139 ts_dest->tv_nsec = 1000 * tv_end->tv_usec;
140 }
142 time_normalize (ts_dest);
143 } /* }}} void time_calc */
145 static void *ping_thread (void *arg) /* {{{ */
146 {
147 static pingobj_t *pingobj = NULL;
149 struct timeval tv_begin;
150 struct timeval tv_end;
151 struct timespec ts_wait;
152 struct timespec ts_int;
154 hostlist_t *hl;
155 int count;
157 pthread_mutex_lock (&ping_lock);
159 pingobj = ping_construct ();
160 if (pingobj == NULL)
161 {
162 ERROR ("ping plugin: ping_construct failed.");
163 ping_thread_error = 1;
164 pthread_mutex_unlock (&ping_lock);
165 return ((void *) -1);
166 }
168 if (ping_source != NULL)
169 if (ping_setopt (pingobj, PING_OPT_SOURCE, (void *) ping_source) != 0)
170 ERROR ("ping plugin: Failed to set source address: %s",
171 ping_get_error (pingobj));
173 #ifdef HAVE_OPING_1_3
174 if (ping_device != NULL)
175 if (ping_setopt (pingobj, PING_OPT_DEVICE, (void *) ping_device) != 0)
176 ERROR ("ping plugin: Failed to set device: %s",
177 ping_get_error (pingobj));
178 #endif
180 ping_setopt (pingobj, PING_OPT_TIMEOUT, (void *) &ping_timeout);
181 ping_setopt (pingobj, PING_OPT_TTL, (void *) &ping_ttl);
183 /* Add all the hosts to the ping object. */
184 count = 0;
185 for (hl = hostlist_head; hl != NULL; hl = hl->next)
186 {
187 int status;
188 status = ping_host_add (pingobj, hl->host);
189 if (status != 0)
190 WARNING ("ping plugin: ping_host_add (%s) failed.", hl->host);
191 else
192 count++;
193 }
195 if (count == 0)
196 {
197 ERROR ("ping plugin: No host could be added to ping object. Giving up.");
198 ping_thread_error = 1;
199 pthread_mutex_unlock (&ping_lock);
200 return ((void *) -1);
201 }
203 /* Set up `ts_int' */
204 {
205 double temp_sec;
206 double temp_nsec;
208 temp_nsec = modf (ping_interval, &temp_sec);
209 ts_int.tv_sec = (time_t) temp_sec;
210 ts_int.tv_nsec = (long) (temp_nsec * 1000000000L);
211 }
213 while (ping_thread_loop > 0)
214 {
215 pingobj_iter_t *iter;
216 int status;
218 if (gettimeofday (&tv_begin, NULL) < 0)
219 {
220 ERROR ("ping plugin: gettimeofday failed");
221 ping_thread_error = 1;
222 break;
223 }
225 pthread_mutex_unlock (&ping_lock);
227 status = ping_send (pingobj);
228 if (status < 0)
229 {
230 ERROR ("ping plugin: ping_send failed: %s", ping_get_error (pingobj));
231 pthread_mutex_lock (&ping_lock);
232 ping_thread_error = 1;
233 break;
234 }
236 pthread_mutex_lock (&ping_lock);
238 if (ping_thread_loop <= 0)
239 break;
241 for (iter = ping_iterator_get (pingobj);
242 iter != NULL;
243 iter = ping_iterator_next (iter))
244 { /* {{{ */
245 char userhost[NI_MAXHOST];
246 double latency;
247 size_t param_size;
249 param_size = sizeof (userhost);
250 status = ping_iterator_get_info (iter,
251 #ifdef PING_INFO_USERNAME
252 PING_INFO_USERNAME,
253 #else
254 PING_INFO_HOSTNAME,
255 #endif
256 userhost, ¶m_size);
257 if (status != 0)
258 {
259 WARNING ("ping plugin: ping_iterator_get_info failed: %s",
260 ping_get_error (pingobj));
261 continue;
262 }
264 for (hl = hostlist_head; hl != NULL; hl = hl->next)
265 if (strcmp (userhost, hl->host) == 0)
266 break;
268 if (hl == NULL)
269 {
270 WARNING ("ping plugin: Cannot find host %s.", userhost);
271 continue;
272 }
274 param_size = sizeof (latency);
275 status = ping_iterator_get_info (iter, PING_INFO_LATENCY,
276 (void *) &latency, ¶m_size);
277 if (status != 0)
278 {
279 WARNING ("ping plugin: ping_iterator_get_info failed: %s",
280 ping_get_error (pingobj));
281 continue;
282 }
284 hl->pkg_sent++;
285 if (latency >= 0.0)
286 {
287 hl->pkg_recv++;
288 hl->latency_total += latency;
289 hl->latency_squared += (latency * latency);
291 /* reset missed packages counter */
292 hl->pkg_missed = 0;
293 } else
294 hl->pkg_missed++;
296 /* if the host did not answer our last N packages, trigger a resolv. */
297 if (ping_max_missed >= 0 && hl->pkg_missed >= ping_max_missed)
298 { /* {{{ */
299 /* we reset the missed package counter here, since we only want to
300 * trigger a resolv every N packages and not every package _AFTER_ N
301 * missed packages */
302 hl->pkg_missed = 0;
304 WARNING ("ping plugin: host %s has not answered %d PING requests,"
305 " triggering resolve", hl->host, ping_max_missed);
307 /* we trigger the resolv simply be removeing and adding the host to our
308 * ping object */
309 status = ping_host_remove (pingobj, hl->host);
310 if (status != 0)
311 {
312 WARNING ("ping plugin: ping_host_remove (%s) failed.", hl->host);
313 }
314 else
315 {
316 status = ping_host_add (pingobj, hl->host);
317 if (status != 0)
318 WARNING ("ping plugin: ping_host_add (%s) failed.", hl->host);
319 }
320 } /* }}} ping_max_missed */
321 } /* }}} for (iter) */
323 if (gettimeofday (&tv_end, NULL) < 0)
324 {
325 ERROR ("ping plugin: gettimeofday failed");
326 ping_thread_error = 1;
327 break;
328 }
330 /* Calculate the absolute time until which to wait and store it in
331 * `ts_wait'. */
332 time_calc (&ts_wait, &ts_int, &tv_begin, &tv_end);
334 status = pthread_cond_timedwait (&ping_cond, &ping_lock, &ts_wait);
335 if (ping_thread_loop <= 0)
336 break;
337 } /* while (ping_thread_loop > 0) */
339 pthread_mutex_unlock (&ping_lock);
340 ping_destroy (pingobj);
342 return ((void *) 0);
343 } /* }}} void *ping_thread */
345 static int start_thread (void) /* {{{ */
346 {
347 int status;
349 pthread_mutex_lock (&ping_lock);
351 if (ping_thread_loop != 0)
352 {
353 pthread_mutex_unlock (&ping_lock);
354 return (-1);
355 }
357 ping_thread_loop = 1;
358 ping_thread_error = 0;
359 status = pthread_create (&ping_thread_id, /* attr = */ NULL,
360 ping_thread, /* arg = */ (void *) 0);
361 if (status != 0)
362 {
363 ping_thread_loop = 0;
364 ERROR ("ping plugin: Starting thread failed.");
365 pthread_mutex_unlock (&ping_lock);
366 return (-1);
367 }
369 pthread_mutex_unlock (&ping_lock);
370 return (0);
371 } /* }}} int start_thread */
373 static int stop_thread (void) /* {{{ */
374 {
375 int status;
377 pthread_mutex_lock (&ping_lock);
379 if (ping_thread_loop == 0)
380 {
381 pthread_mutex_unlock (&ping_lock);
382 return (-1);
383 }
385 ping_thread_loop = 0;
386 pthread_cond_broadcast (&ping_cond);
387 pthread_mutex_unlock (&ping_lock);
389 status = pthread_join (ping_thread_id, /* return = */ NULL);
390 if (status != 0)
391 {
392 ERROR ("ping plugin: Stopping thread failed.");
393 status = -1;
394 }
396 memset (&ping_thread_id, 0, sizeof (ping_thread_id));
397 ping_thread_error = 0;
399 return (status);
400 } /* }}} int stop_thread */
402 static int ping_init (void) /* {{{ */
403 {
404 if (hostlist_head == NULL)
405 {
406 NOTICE ("ping plugin: No hosts have been configured.");
407 return (-1);
408 }
410 if (ping_timeout > ping_interval)
411 {
412 ping_timeout = 0.9 * ping_interval;
413 WARNING ("ping plugin: Timeout is greater than interval. "
414 "Will use a timeout of %gs.", ping_timeout);
415 }
417 if (start_thread () != 0)
418 return (-1);
420 return (0);
421 } /* }}} int ping_init */
423 static int config_set_string (const char *name, /* {{{ */
424 char **var, const char *value)
425 {
426 char *tmp;
428 tmp = strdup (value);
429 if (tmp == NULL)
430 {
431 char errbuf[1024];
432 ERROR ("ping plugin: Setting `%s' to `%s' failed: strdup failed: %s",
433 name, value, sstrerror (errno, errbuf, sizeof (errbuf)));
434 return (1);
435 }
437 if (*var != NULL)
438 free (*var);
439 *var = tmp;
440 return (0);
441 } /* }}} int config_set_string */
443 static int ping_config (const char *key, const char *value) /* {{{ */
444 {
445 if (strcasecmp (key, "Host") == 0)
446 {
447 hostlist_t *hl;
448 char *host;
450 hl = (hostlist_t *) malloc (sizeof (hostlist_t));
451 if (hl == NULL)
452 {
453 char errbuf[1024];
454 ERROR ("ping plugin: malloc failed: %s",
455 sstrerror (errno, errbuf, sizeof (errbuf)));
456 return (1);
457 }
459 host = strdup (value);
460 if (host == NULL)
461 {
462 char errbuf[1024];
463 sfree (hl);
464 ERROR ("ping plugin: strdup failed: %s",
465 sstrerror (errno, errbuf, sizeof (errbuf)));
466 return (1);
467 }
469 hl->host = host;
470 hl->pkg_sent = 0;
471 hl->pkg_recv = 0;
472 hl->pkg_missed = 0;
473 hl->latency_total = 0.0;
474 hl->latency_squared = 0.0;
475 hl->next = hostlist_head;
476 hostlist_head = hl;
477 }
478 else if (strcasecmp (key, "SourceAddress") == 0)
479 {
480 int status = config_set_string (key, &ping_source, value);
481 if (status != 0)
482 return (status);
483 }
484 #ifdef HAVE_OPING_1_3
485 else if (strcasecmp (key, "Device") == 0)
486 {
487 int status = config_set_string (key, &ping_device, value);
488 if (status != 0)
489 return (status);
490 }
491 #endif
492 else if (strcasecmp (key, "TTL") == 0)
493 {
494 int ttl = atoi (value);
495 if ((ttl > 0) && (ttl <= 255))
496 ping_ttl = ttl;
497 else
498 WARNING ("ping plugin: Ignoring invalid TTL %i.", ttl);
499 }
500 else if (strcasecmp (key, "Interval") == 0)
501 {
502 double tmp;
504 tmp = atof (value);
505 if (tmp > 0.0)
506 ping_interval = tmp;
507 else
508 WARNING ("ping plugin: Ignoring invalid interval %g (%s)",
509 tmp, value);
510 }
511 else if (strcasecmp (key, "Timeout") == 0)
512 {
513 double tmp;
515 tmp = atof (value);
516 if (tmp > 0.0)
517 ping_timeout = tmp;
518 else
519 WARNING ("ping plugin: Ignoring invalid timeout %g (%s)",
520 tmp, value);
521 }
522 else if (strcasecmp (key, "MaxMissed") == 0)
523 {
524 ping_max_missed = atoi (value);
525 if (ping_max_missed < 0)
526 INFO ("ping plugin: MaxMissed < 0, disabled re-resolving of hosts");
527 }
528 else
529 {
530 return (-1);
531 }
533 return (0);
534 } /* }}} int ping_config */
536 static void submit (const char *host, const char *type, /* {{{ */
537 gauge_t value)
538 {
539 value_t values[1];
540 value_list_t vl = VALUE_LIST_INIT;
542 values[0].gauge = value;
544 vl.values = values;
545 vl.values_len = 1;
546 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
547 sstrncpy (vl.plugin, "ping", sizeof (vl.plugin));
548 sstrncpy (vl.plugin_instance, "", sizeof (vl.plugin_instance));
549 sstrncpy (vl.type_instance, host, sizeof (vl.type_instance));
550 sstrncpy (vl.type, type, sizeof (vl.type));
552 plugin_dispatch_values (&vl);
553 } /* }}} void ping_submit */
555 static int ping_read (void) /* {{{ */
556 {
557 hostlist_t *hl;
559 if (ping_thread_error != 0)
560 {
561 ERROR ("ping plugin: The ping thread had a problem. Restarting it.");
563 stop_thread ();
565 for (hl = hostlist_head; hl != NULL; hl = hl->next)
566 {
567 hl->pkg_sent = 0;
568 hl->pkg_recv = 0;
569 hl->latency_total = 0.0;
570 hl->latency_squared = 0.0;
571 }
573 start_thread ();
575 return (-1);
576 } /* if (ping_thread_error != 0) */
578 for (hl = hostlist_head; hl != NULL; hl = hl->next) /* {{{ */
579 {
580 uint32_t pkg_sent;
581 uint32_t pkg_recv;
582 double latency_total;
583 double latency_squared;
585 double latency_average;
586 double latency_stddev;
588 double droprate;
590 /* Locking here works, because the structure of the linked list is only
591 * changed during configure and shutdown. */
592 pthread_mutex_lock (&ping_lock);
594 pkg_sent = hl->pkg_sent;
595 pkg_recv = hl->pkg_recv;
596 latency_total = hl->latency_total;
597 latency_squared = hl->latency_squared;
599 hl->pkg_sent = 0;
600 hl->pkg_recv = 0;
601 hl->latency_total = 0.0;
602 hl->latency_squared = 0.0;
604 pthread_mutex_unlock (&ping_lock);
606 /* This e. g. happens when starting up. */
607 if (pkg_sent == 0)
608 {
609 DEBUG ("ping plugin: No packages for host %s have been sent.",
610 hl->host);
611 continue;
612 }
614 /* Calculate average. Beware of division by zero. */
615 if (pkg_recv == 0)
616 latency_average = NAN;
617 else
618 latency_average = latency_total / ((double) pkg_recv);
620 /* Calculate standard deviation. Beware even more of division by zero. */
621 if (pkg_recv == 0)
622 latency_stddev = NAN;
623 else if (pkg_recv == 1)
624 latency_stddev = 0.0;
625 else
626 latency_stddev = sqrt (((((double) pkg_recv) * latency_squared)
627 - (latency_total * latency_total))
628 / ((double) (pkg_recv * (pkg_recv - 1))));
630 /* Calculate drop rate. */
631 droprate = ((double) (pkg_sent - pkg_recv)) / ((double) pkg_sent);
633 submit (hl->host, "ping", latency_average);
634 submit (hl->host, "ping_stddev", latency_stddev);
635 submit (hl->host, "ping_droprate", droprate);
636 } /* }}} for (hl = hostlist_head; hl != NULL; hl = hl->next) */
638 return (0);
639 } /* }}} int ping_read */
641 static int ping_shutdown (void) /* {{{ */
642 {
643 hostlist_t *hl;
645 INFO ("ping plugin: Shutting down thread.");
646 if (stop_thread () < 0)
647 return (-1);
649 hl = hostlist_head;
650 while (hl != NULL)
651 {
652 hostlist_t *hl_next;
654 hl_next = hl->next;
656 sfree (hl->host);
657 sfree (hl);
659 hl = hl_next;
660 }
662 return (0);
663 } /* }}} int ping_shutdown */
665 void module_register (void)
666 {
667 plugin_register_config ("ping", ping_config,
668 config_keys, config_keys_num);
669 plugin_register_init ("ping", ping_init);
670 plugin_register_read ("ping", ping_read);
671 plugin_register_shutdown ("ping", ping_shutdown);
672 } /* void module_register */
674 /* vim: set sw=2 sts=2 et fdm=marker : */