1 /**
2 * collectd - src/utils_cache.c
3 * Copyright (C) 2007,2008 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 * Author:
19 * Florian octo Forster <octo at verplant.org>
20 **/
22 #include "collectd.h"
23 #include "common.h"
24 #include "plugin.h"
25 #include "utils_avltree.h"
26 #include "utils_cache.h"
27 #include "utils_threshold.h"
29 #include <assert.h>
30 #include <pthread.h>
32 typedef struct cache_entry_s
33 {
34 char name[6 * DATA_MAX_NAME_LEN];
35 int values_num;
36 gauge_t *values_gauge;
37 value_t *values_raw;
38 /* Time contained in the package
39 * (for calculating rates) */
40 time_t last_time;
41 /* Time according to the local clock
42 * (for purging old entries) */
43 time_t last_update;
44 /* Interval in which the data is collected
45 * (for purding old entries) */
46 int interval;
47 int state;
48 } cache_entry_t;
50 static c_avl_tree_t *cache_tree = NULL;
51 static pthread_mutex_t cache_lock = PTHREAD_MUTEX_INITIALIZER;
53 static int cache_compare (const cache_entry_t *a, const cache_entry_t *b)
54 {
55 assert ((a != NULL) && (b != NULL));
56 return (strcmp (a->name, b->name));
57 } /* int cache_compare */
59 static cache_entry_t *cache_alloc (int values_num)
60 {
61 cache_entry_t *ce;
63 ce = (cache_entry_t *) malloc (sizeof (cache_entry_t));
64 if (ce == NULL)
65 {
66 ERROR ("utils_cache: cache_alloc: malloc failed.");
67 return (NULL);
68 }
69 memset (ce, '\0', sizeof (cache_entry_t));
70 ce->values_num = values_num;
72 ce->values_gauge = calloc (values_num, sizeof (*ce->values_gauge));
73 ce->values_raw = calloc (values_num, sizeof (*ce->values_raw));
74 if ((ce->values_gauge == NULL) || (ce->values_raw == NULL))
75 {
76 sfree (ce->values_gauge);
77 sfree (ce->values_raw);
78 sfree (ce);
79 ERROR ("utils_cache: cache_alloc: calloc failed.");
80 return (NULL);
81 }
83 return (ce);
84 } /* cache_entry_t *cache_alloc */
86 static void cache_free (cache_entry_t *ce)
87 {
88 if (ce == NULL)
89 return;
91 sfree (ce->values_gauge);
92 sfree (ce->values_raw);
93 sfree (ce);
94 } /* void cache_free */
96 static int uc_send_notification (const char *name)
97 {
98 cache_entry_t *ce = NULL;
99 int status;
101 char *name_copy;
102 char *host;
103 char *plugin;
104 char *plugin_instance;
105 char *type;
106 char *type_instance;
108 notification_t n;
110 name_copy = strdup (name);
111 if (name_copy == NULL)
112 {
113 ERROR ("uc_send_notification: strdup failed.");
114 return (-1);
115 }
117 status = parse_identifier (name_copy, &host,
118 &plugin, &plugin_instance,
119 &type, &type_instance);
120 if (status != 0)
121 {
122 ERROR ("uc_send_notification: Cannot parse name `%s'", name);
123 return (-1);
124 }
126 /* Copy the associative members */
127 notification_init (&n, NOTIF_FAILURE, /* host = */ NULL,
128 host, plugin, plugin_instance, type, type_instance);
130 sfree (name_copy);
131 name_copy = host = plugin = plugin_instance = type = type_instance = NULL;
133 pthread_mutex_lock (&cache_lock);
135 /*
136 * Set the time _after_ getting the lock because we don't know how long
137 * acquiring the lock takes and we will use this time later to decide
138 * whether or not the state is OKAY.
139 */
140 n.time = time (NULL);
142 status = c_avl_get (cache_tree, name, (void *) &ce);
143 if (status != 0)
144 {
145 pthread_mutex_unlock (&cache_lock);
146 sfree (name_copy);
147 return (-1);
148 }
150 /* Check if the entry has been updated in the meantime */
151 if ((n.time - ce->last_update) < (2 * ce->interval))
152 {
153 ce->state = STATE_OKAY;
154 pthread_mutex_unlock (&cache_lock);
155 sfree (name_copy);
156 return (-1);
157 }
159 ssnprintf (n.message, sizeof (n.message),
160 "%s has not been updated for %i seconds.", name,
161 (int) (n.time - ce->last_update));
163 pthread_mutex_unlock (&cache_lock);
165 plugin_dispatch_notification (&n);
167 return (0);
168 } /* int uc_send_notification */
170 static void uc_check_range (const data_set_t *ds, cache_entry_t *ce)
171 {
172 int i;
174 for (i = 0; i < ds->ds_num; i++)
175 {
176 if (isnan (ce->values_gauge[i]))
177 continue;
178 else if (ce->values_gauge[i] < ds->ds[i].min)
179 ce->values_gauge[i] = NAN;
180 else if (ce->values_gauge[i] > ds->ds[i].max)
181 ce->values_gauge[i] = NAN;
182 }
183 } /* void uc_check_range */
185 static int uc_insert (const data_set_t *ds, const value_list_t *vl,
186 const char *key)
187 {
188 int i;
189 char *key_copy;
190 cache_entry_t *ce;
192 /* `cache_lock' has been locked by `uc_update' */
194 key_copy = strdup (key);
195 if (key_copy == NULL)
196 {
197 ERROR ("uc_insert: strdup failed.");
198 return (-1);
199 }
201 ce = cache_alloc (ds->ds_num);
202 if (ce == NULL)
203 {
204 sfree (key_copy);
205 ERROR ("uc_insert: cache_alloc (%i) failed.", ds->ds_num);
206 return (-1);
207 }
209 sstrncpy (ce->name, key, sizeof (ce->name));
211 for (i = 0; i < ds->ds_num; i++)
212 {
213 switch (ds->ds[i].type)
214 {
215 case DS_TYPE_COUNTER:
216 ce->values_gauge[i] = NAN;
217 ce->values_raw[i].counter = vl->values[i].counter;
218 break;
220 case DS_TYPE_GAUGE:
221 ce->values_gauge[i] = vl->values[i].gauge;
222 ce->values_raw[i].gauge = vl->values[i].gauge;
223 break;
225 case DS_TYPE_DERIVE:
226 ce->values_gauge[i] = NAN;
227 ce->values_raw[i].derive = vl->values[i].derive;
228 break;
230 case DS_TYPE_ABSOLUTE:
231 ce->values_gauge[i] = NAN;
232 if (vl->interval > 0)
233 ce->values_gauge[i] = ((double) vl->values[i].absolute)
234 / ((double) vl->interval);
235 ce->values_raw[i].absolute = vl->values[i].absolute;
236 break;
238 default:
239 /* This shouldn't happen. */
240 ERROR ("uc_insert: Don't know how to handle data source type %i.",
241 ds->ds[i].type);
242 return (-1);
243 } /* switch (ds->ds[i].type) */
244 } /* for (i) */
246 /* Prune invalid gauge data */
247 uc_check_range (ds, ce);
249 ce->last_time = vl->time;
250 ce->last_update = time (NULL);
251 ce->interval = vl->interval;
252 ce->state = STATE_OKAY;
254 if (c_avl_insert (cache_tree, key_copy, ce) != 0)
255 {
256 sfree (key_copy);
257 ERROR ("uc_insert: c_avl_insert failed.");
258 return (-1);
259 }
261 DEBUG ("uc_insert: Added %s to the cache.", key);
262 return (0);
263 } /* int uc_insert */
265 int uc_init (void)
266 {
267 if (cache_tree == NULL)
268 cache_tree = c_avl_create ((int (*) (const void *, const void *))
269 cache_compare);
271 return (0);
272 } /* int uc_init */
274 int uc_check_timeout (void)
275 {
276 time_t now;
277 cache_entry_t *ce;
279 char **keys = NULL;
280 int keys_len = 0;
282 char *key;
283 c_avl_iterator_t *iter;
284 int i;
286 pthread_mutex_lock (&cache_lock);
288 now = time (NULL);
290 /* Build a list of entries to be flushed */
291 iter = c_avl_get_iterator (cache_tree);
292 while (c_avl_iterator_next (iter, (void *) &key, (void *) &ce) == 0)
293 {
294 /* If entry has not been updated, add to `keys' array */
295 if ((now - ce->last_update) >= (2 * ce->interval))
296 {
297 char **tmp;
299 tmp = (char **) realloc ((void *) keys,
300 (keys_len + 1) * sizeof (char *));
301 if (tmp == NULL)
302 {
303 ERROR ("uc_check_timeout: realloc failed.");
304 c_avl_iterator_destroy (iter);
305 sfree (keys);
306 pthread_mutex_unlock (&cache_lock);
307 return (-1);
308 }
310 keys = tmp;
311 keys[keys_len] = strdup (key);
312 if (keys[keys_len] == NULL)
313 {
314 ERROR ("uc_check_timeout: strdup failed.");
315 continue;
316 }
317 keys_len++;
318 }
319 } /* while (c_avl_iterator_next) */
321 ce = NULL;
323 for (i = 0; i < keys_len; i++)
324 {
325 int status;
327 status = ut_check_interesting (keys[i]);
329 if (status < 0)
330 {
331 ERROR ("uc_check_timeout: ut_check_interesting failed.");
332 sfree (keys[i]);
333 continue;
334 }
335 else if (status == 0) /* ``service'' is uninteresting */
336 {
337 DEBUG ("uc_check_timeout: %s is missing but ``uninteresting''",
338 keys[i]);
339 status = c_avl_remove (cache_tree, keys[i],
340 (void *) &key, (void *) &ce);
341 if (status != 0)
342 {
343 ERROR ("uc_check_timeout: c_avl_remove (%s) failed.", keys[i]);
344 }
345 sfree (keys[i]);
346 sfree (key);
347 cache_free (ce);
348 continue;
349 }
351 /* If we get here, the value is ``interesting''. Query the record from the
352 * cache and update the state field. */
353 if (c_avl_get (cache_tree, keys[i], (void *) &ce) != 0)
354 {
355 ERROR ("uc_check_timeout: cannot get data for %s from cache", keys[i]);
356 /* Do not free `keys[i]' so a notification is sent further down. */
357 continue;
358 }
359 assert (ce != NULL);
361 if (status == 2) /* persist */
362 {
363 DEBUG ("uc_check_timeout: %s is missing, sending notification.",
364 keys[i]);
365 ce->state = STATE_MISSING;
366 /* Do not free `keys[i]' so a notification is sent further down. */
367 }
368 else if (status == 1) /* do not persist */
369 {
370 if (ce->state == STATE_MISSING)
371 {
372 DEBUG ("uc_check_timeout: %s is missing but "
373 "notification has already been sent.",
374 keys[i]);
375 /* Set `keys[i]' to NULL to no notification is sent. */
376 sfree (keys[i]);
377 }
378 else /* (ce->state != STATE_MISSING) */
379 {
380 DEBUG ("uc_check_timeout: %s is missing, sending one notification.",
381 keys[i]);
382 ce->state = STATE_MISSING;
383 /* Do not free `keys[i]' so a notification is sent further down. */
384 }
385 }
386 else
387 {
388 WARNING ("uc_check_timeout: ut_check_interesting (%s) returned "
389 "invalid status %i.",
390 keys[i], status);
391 sfree (keys[i]);
392 }
394 /* Make really sure the next iteration doesn't work with this pointer.
395 * There have been too many bugs in the past.. :/ -- octo */
396 ce = NULL;
397 } /* for (keys[i]) */
399 c_avl_iterator_destroy (iter);
401 pthread_mutex_unlock (&cache_lock);
403 for (i = 0; i < keys_len; i++)
404 {
405 if (keys[i] == NULL)
406 continue;
408 uc_send_notification (keys[i]);
409 sfree (keys[i]);
410 }
412 sfree (keys);
414 return (0);
415 } /* int uc_check_timeout */
417 int uc_update (const data_set_t *ds, const value_list_t *vl)
418 {
419 char name[6 * DATA_MAX_NAME_LEN];
420 cache_entry_t *ce = NULL;
421 int send_okay_notification = 0;
422 time_t update_delay = 0;
423 notification_t n;
424 int status;
425 int i;
427 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
428 {
429 ERROR ("uc_update: FORMAT_VL failed.");
430 return (-1);
431 }
433 pthread_mutex_lock (&cache_lock);
435 status = c_avl_get (cache_tree, name, (void *) &ce);
436 if (status != 0) /* entry does not yet exist */
437 {
438 status = uc_insert (ds, vl, name);
439 pthread_mutex_unlock (&cache_lock);
440 return (status);
441 }
443 assert (ce != NULL);
444 assert (ce->values_num == ds->ds_num);
446 if (ce->last_time >= vl->time)
447 {
448 pthread_mutex_unlock (&cache_lock);
449 NOTICE ("uc_update: Value too old: name = %s; value time = %u; "
450 "last cache update = %u;",
451 name, (unsigned int) vl->time, (unsigned int) ce->last_time);
452 return (-1);
453 }
455 /* Send a notification (after the lock has been released) if we switch the
456 * state from something else to `okay'. */
457 if (ce->state == STATE_MISSING)
458 {
459 send_okay_notification = 1;
460 ce->state = STATE_OKAY;
461 update_delay = time (NULL) - ce->last_update;
462 }
464 for (i = 0; i < ds->ds_num; i++)
465 {
466 switch (ds->ds[i].type)
467 {
468 case DS_TYPE_COUNTER:
469 {
470 counter_t diff;
472 /* check if the counter has wrapped around */
473 if (vl->values[i].counter < ce->values_raw[i].counter)
474 {
475 if (ce->values_raw[i].counter <= 4294967295U)
476 diff = (4294967295U - ce->values_raw[i].counter)
477 + vl->values[i].counter;
478 else
479 diff = (18446744073709551615ULL - ce->values_raw[i].counter)
480 + vl->values[i].counter;
481 }
482 else /* counter has NOT wrapped around */
483 {
484 diff = vl->values[i].counter - ce->values_raw[i].counter;
485 }
487 ce->values_gauge[i] = ((double) diff)
488 / ((double) (vl->time - ce->last_time));
489 ce->values_raw[i].counter = vl->values[i].counter;
490 }
491 break;
493 case DS_TYPE_GAUGE:
494 ce->values_raw[i].gauge = vl->values[i].gauge;
495 ce->values_gauge[i] = vl->values[i].gauge;
496 break;
498 case DS_TYPE_DERIVE:
499 {
500 derive_t diff;
502 diff = vl->values[i].derive - ce->values_raw[i].derive;
504 ce->values_gauge[i] = ((double) diff)
505 / ((double) (vl->time - ce->last_time));
506 ce->values_raw[i].derive = vl->values[i].derive;
507 }
508 break;
510 case DS_TYPE_ABSOLUTE:
511 ce->values_gauge[i] = ((double) vl->values[i].absolute)
512 / ((double) (vl->time - ce->last_time));
513 ce->values_raw[i].absolute = vl->values[i].absolute;
514 break;
516 default:
517 /* This shouldn't happen. */
518 pthread_mutex_unlock (&cache_lock);
519 ERROR ("uc_update: Don't know how to handle data source type %i.",
520 ds->ds[i].type);
521 return (-1);
522 } /* switch (ds->ds[i].type) */
524 DEBUG ("uc_update: %s: ds[%i] = %lf", name, i, ce->values_gauge[i]);
525 } /* for (i) */
527 /* Prune invalid gauge data */
528 uc_check_range (ds, ce);
530 ce->last_time = vl->time;
531 ce->last_update = time (NULL);
532 ce->interval = vl->interval;
534 pthread_mutex_unlock (&cache_lock);
536 if (send_okay_notification == 0)
537 return (0);
539 /* Do not send okay notifications for uninteresting values, i. e. values for
540 * which no threshold is configured. */
541 status = ut_check_interesting (name);
542 if (status <= 0)
543 return (0);
545 /* Initialize the notification */
546 memset (&n, '\0', sizeof (n));
547 NOTIFICATION_INIT_VL (&n, vl, ds);
549 n.severity = NOTIF_OKAY;
550 n.time = vl->time;
552 ssnprintf (n.message, sizeof (n.message),
553 "Received a value for %s. It was missing for %u seconds.",
554 name, (unsigned int) update_delay);
556 plugin_dispatch_notification (&n);
558 return (0);
559 } /* int uc_update */
561 int uc_get_rate_by_name (const char *name, gauge_t **ret_values, size_t *ret_values_num)
562 {
563 gauge_t *ret = NULL;
564 size_t ret_num = 0;
565 cache_entry_t *ce = NULL;
566 int status = 0;
568 pthread_mutex_lock (&cache_lock);
570 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
571 {
572 assert (ce != NULL);
574 ret_num = ce->values_num;
575 ret = (gauge_t *) malloc (ret_num * sizeof (gauge_t));
576 if (ret == NULL)
577 {
578 ERROR ("utils_cache: uc_get_rate_by_name: malloc failed.");
579 status = -1;
580 }
581 else
582 {
583 memcpy (ret, ce->values_gauge, ret_num * sizeof (gauge_t));
584 }
585 }
586 else
587 {
588 DEBUG ("utils_cache: uc_get_rate_by_name: No such value: %s", name);
589 status = -1;
590 }
592 pthread_mutex_unlock (&cache_lock);
594 if (status == 0)
595 {
596 *ret_values = ret;
597 *ret_values_num = ret_num;
598 }
600 return (status);
601 } /* gauge_t *uc_get_rate_by_name */
603 gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
604 {
605 char name[6 * DATA_MAX_NAME_LEN];
606 gauge_t *ret = NULL;
607 size_t ret_num = 0;
608 int status;
610 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
611 {
612 ERROR ("utils_cache: uc_get_rate: FORMAT_VL failed.");
613 return (NULL);
614 }
616 status = uc_get_rate_by_name (name, &ret, &ret_num);
617 if (status != 0)
618 return (NULL);
620 /* This is important - the caller has no other way of knowing how many
621 * values are returned. */
622 if (ret_num != (size_t) ds->ds_num)
623 {
624 ERROR ("utils_cache: uc_get_rate: ds[%s] has %i values, "
625 "but uc_get_rate_by_name returned %zu.",
626 ds->type, ds->ds_num, ret_num);
627 sfree (ret);
628 return (NULL);
629 }
631 return (ret);
632 } /* gauge_t *uc_get_rate */
634 int uc_get_names (char ***ret_names, time_t **ret_times, size_t *ret_number)
635 {
636 c_avl_iterator_t *iter;
637 char *key;
638 cache_entry_t *value;
640 char **names = NULL;
641 time_t *times = NULL;
642 size_t number = 0;
644 int status = 0;
646 if ((ret_names == NULL) || (ret_number == NULL))
647 return (-1);
649 pthread_mutex_lock (&cache_lock);
651 iter = c_avl_get_iterator (cache_tree);
652 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
653 {
654 char **temp;
656 if (ret_times != NULL)
657 {
658 time_t *tmp_times;
660 tmp_times = (time_t *) realloc (times, sizeof (time_t) * (number + 1));
661 if (tmp_times == NULL)
662 {
663 status = -1;
664 break;
665 }
666 times = tmp_times;
667 times[number] = value->last_time;
668 }
670 temp = (char **) realloc (names, sizeof (char *) * (number + 1));
671 if (temp == NULL)
672 {
673 status = -1;
674 break;
675 }
676 names = temp;
677 names[number] = strdup (key);
678 if (names[number] == NULL)
679 {
680 status = -1;
681 break;
682 }
683 number++;
684 } /* while (c_avl_iterator_next) */
686 c_avl_iterator_destroy (iter);
687 pthread_mutex_unlock (&cache_lock);
689 if (status != 0)
690 {
691 size_t i;
693 for (i = 0; i < number; i++)
694 {
695 sfree (names[i]);
696 }
697 sfree (names);
699 return (-1);
700 }
702 *ret_names = names;
703 if (ret_times != NULL)
704 *ret_times = times;
705 *ret_number = number;
707 return (0);
708 } /* int uc_get_names */
710 int uc_get_state (const data_set_t *ds, const value_list_t *vl)
711 {
712 char name[6 * DATA_MAX_NAME_LEN];
713 cache_entry_t *ce = NULL;
714 int ret = STATE_ERROR;
716 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
717 {
718 ERROR ("uc_get_state: FORMAT_VL failed.");
719 return (STATE_ERROR);
720 }
722 pthread_mutex_lock (&cache_lock);
724 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
725 {
726 assert (ce != NULL);
727 ret = ce->state;
728 }
730 pthread_mutex_unlock (&cache_lock);
732 return (ret);
733 } /* int uc_get_state */
735 int uc_set_state (const data_set_t *ds, const value_list_t *vl, int state)
736 {
737 char name[6 * DATA_MAX_NAME_LEN];
738 cache_entry_t *ce = NULL;
739 int ret = -1;
741 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
742 {
743 ERROR ("uc_get_state: FORMAT_VL failed.");
744 return (STATE_ERROR);
745 }
747 pthread_mutex_lock (&cache_lock);
749 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
750 {
751 assert (ce != NULL);
752 ret = ce->state;
753 ce->state = state;
754 }
756 pthread_mutex_unlock (&cache_lock);
758 return (ret);
759 } /* int uc_set_state */
760 /* vim: set sw=2 ts=8 sts=2 tw=78 : */