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 counter_t *values_counter;
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 = (gauge_t *) calloc (values_num, sizeof (gauge_t));
73 ce->values_counter = (counter_t *) calloc (values_num, sizeof (counter_t));
74 if ((ce->values_gauge == NULL) || (ce->values_counter == NULL))
75 {
76 sfree (ce->values_gauge);
77 sfree (ce->values_counter);
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_counter);
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 int uc_insert (const data_set_t *ds, const value_list_t *vl,
171 const char *key)
172 {
173 int i;
174 char *key_copy;
175 cache_entry_t *ce;
177 /* `cache_lock' has been locked by `uc_update' */
179 key_copy = strdup (key);
180 if (key_copy == NULL)
181 {
182 ERROR ("uc_insert: strdup failed.");
183 return (-1);
184 }
186 ce = cache_alloc (ds->ds_num);
187 if (ce == NULL)
188 {
189 sfree (key_copy);
190 ERROR ("uc_insert: cache_alloc (%i) failed.", ds->ds_num);
191 return (-1);
192 }
194 sstrncpy (ce->name, key, sizeof (ce->name));
196 for (i = 0; i < ds->ds_num; i++)
197 {
198 if (ds->ds[i].type == DS_TYPE_COUNTER)
199 {
200 ce->values_gauge[i] = NAN;
201 ce->values_counter[i] = vl->values[i].counter;
202 }
203 else /* if (ds->ds[i].type == DS_TYPE_GAUGE) */
204 {
205 ce->values_gauge[i] = vl->values[i].gauge;
206 }
207 } /* for (i) */
209 ce->last_time = vl->time;
210 ce->last_update = time (NULL);
211 ce->interval = vl->interval;
212 ce->state = STATE_OKAY;
214 if (c_avl_insert (cache_tree, key_copy, ce) != 0)
215 {
216 sfree (key_copy);
217 ERROR ("uc_insert: c_avl_insert failed.");
218 return (-1);
219 }
221 DEBUG ("uc_insert: Added %s to the cache.", key);
222 return (0);
223 } /* int uc_insert */
225 int uc_init (void)
226 {
227 if (cache_tree == NULL)
228 cache_tree = c_avl_create ((int (*) (const void *, const void *))
229 cache_compare);
231 return (0);
232 } /* int uc_init */
234 int uc_check_timeout (void)
235 {
236 time_t now;
237 cache_entry_t *ce;
239 char **keys = NULL;
240 int keys_len = 0;
242 char *key;
243 c_avl_iterator_t *iter;
244 int i;
246 pthread_mutex_lock (&cache_lock);
248 now = time (NULL);
250 /* Build a list of entries to be flushed */
251 iter = c_avl_get_iterator (cache_tree);
252 while (c_avl_iterator_next (iter, (void *) &key, (void *) &ce) == 0)
253 {
254 /* If entry has not been updated, add to `keys' array */
255 if ((now - ce->last_update) >= (2 * ce->interval))
256 {
257 char **tmp;
259 tmp = (char **) realloc ((void *) keys,
260 (keys_len + 1) * sizeof (char *));
261 if (tmp == NULL)
262 {
263 ERROR ("uc_check_timeout: realloc failed.");
264 c_avl_iterator_destroy (iter);
265 sfree (keys);
266 pthread_mutex_unlock (&cache_lock);
267 return (-1);
268 }
270 keys = tmp;
271 keys[keys_len] = strdup (key);
272 if (keys[keys_len] == NULL)
273 {
274 ERROR ("uc_check_timeout: strdup failed.");
275 continue;
276 }
277 keys_len++;
278 }
279 } /* while (c_avl_iterator_next) */
281 ce = NULL;
283 for (i = 0; i < keys_len; i++)
284 {
285 int status;
287 status = ut_check_interesting (keys[i]);
289 if (status < 0)
290 {
291 ERROR ("uc_check_timeout: ut_check_interesting failed.");
292 sfree (keys[i]);
293 continue;
294 }
295 else if (status == 0) /* ``service'' is uninteresting */
296 {
297 DEBUG ("uc_check_timeout: %s is missing but ``uninteresting''",
298 keys[i]);
299 status = c_avl_remove (cache_tree, keys[i],
300 (void *) &key, (void *) &ce);
301 if (status != 0)
302 {
303 ERROR ("uc_check_timeout: c_avl_remove (%s) failed.", keys[i]);
304 }
305 sfree (keys[i]);
306 sfree (key);
307 cache_free (ce);
308 continue;
309 }
311 /* If we get here, the value is ``interesting''. Query the record from the
312 * cache and update the state field. */
313 if (c_avl_get (cache_tree, keys[i], (void *) &ce) != 0)
314 {
315 ERROR ("uc_check_timeout: cannot get data for %s from cache", keys[i]);
316 /* Do not free `keys[i]' so a notification is sent further down. */
317 continue;
318 }
319 assert (ce != NULL);
321 if (status == 2) /* persist */
322 {
323 DEBUG ("uc_check_timeout: %s is missing, sending notification.",
324 keys[i]);
325 ce->state = STATE_MISSING;
326 /* Do not free `keys[i]' so a notification is sent further down. */
327 }
328 else if (status == 1) /* do not persist */
329 {
330 if (ce->state == STATE_MISSING)
331 {
332 DEBUG ("uc_check_timeout: %s is missing but "
333 "notification has already been sent.",
334 keys[i]);
335 /* Set `keys[i]' to NULL to no notification is sent. */
336 sfree (keys[i]);
337 }
338 else /* (ce->state != STATE_MISSING) */
339 {
340 DEBUG ("uc_check_timeout: %s is missing, sending one notification.",
341 keys[i]);
342 ce->state = STATE_MISSING;
343 /* Do not free `keys[i]' so a notification is sent further down. */
344 }
345 }
346 else
347 {
348 WARNING ("uc_check_timeout: ut_check_interesting (%s) returned "
349 "invalid status %i.",
350 keys[i], status);
351 sfree (keys[i]);
352 }
353 } /* for (keys[i]) */
355 c_avl_iterator_destroy (iter);
357 pthread_mutex_unlock (&cache_lock);
359 for (i = 0; i < keys_len; i++)
360 {
361 if (keys[i] == NULL)
362 continue;
364 uc_send_notification (keys[i]);
365 sfree (keys[i]);
366 }
368 sfree (keys);
370 return (0);
371 } /* int uc_check_timeout */
373 int uc_update (const data_set_t *ds, const value_list_t *vl)
374 {
375 char name[6 * DATA_MAX_NAME_LEN];
376 cache_entry_t *ce = NULL;
377 int send_okay_notification = 0;
378 time_t update_delay = 0;
379 notification_t n;
380 int status;
381 int i;
383 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
384 {
385 ERROR ("uc_update: FORMAT_VL failed.");
386 return (-1);
387 }
389 pthread_mutex_lock (&cache_lock);
391 status = c_avl_get (cache_tree, name, (void *) &ce);
392 if (status != 0) /* entry does not yet exist */
393 {
394 status = uc_insert (ds, vl, name);
395 pthread_mutex_unlock (&cache_lock);
396 return (status);
397 }
399 assert (ce != NULL);
400 assert (ce->values_num == ds->ds_num);
402 if (ce->last_time >= vl->time)
403 {
404 pthread_mutex_unlock (&cache_lock);
405 NOTICE ("uc_update: Value too old: name = %s; value time = %u; "
406 "last cache update = %u;",
407 name, (unsigned int) vl->time, (unsigned int) ce->last_time);
408 return (-1);
409 }
411 /* Send a notification (after the lock has been released) if we switch the
412 * state from something else to `okay'. */
413 if (ce->state == STATE_MISSING)
414 {
415 send_okay_notification = 1;
416 ce->state = STATE_OKAY;
417 update_delay = time (NULL) - ce->last_update;
418 }
420 for (i = 0; i < ds->ds_num; i++)
421 {
422 if (ds->ds[i].type == DS_TYPE_COUNTER)
423 {
424 counter_t diff;
426 /* check if the counter has wrapped around */
427 if (vl->values[i].counter < ce->values_counter[i])
428 {
429 if (ce->values_counter[i] <= 4294967295U)
430 diff = (4294967295U - ce->values_counter[i])
431 + vl->values[i].counter;
432 else
433 diff = (18446744073709551615ULL - ce->values_counter[i])
434 + vl->values[i].counter;
435 }
436 else /* counter has NOT wrapped around */
437 {
438 diff = vl->values[i].counter - ce->values_counter[i];
439 }
441 ce->values_gauge[i] = ((double) diff)
442 / ((double) (vl->time - ce->last_time));
443 ce->values_counter[i] = vl->values[i].counter;
444 }
445 else /* if (ds->ds[i].type == DS_TYPE_GAUGE) */
446 {
447 ce->values_gauge[i] = vl->values[i].gauge;
448 }
449 DEBUG ("uc_update: %s: ds[%i] = %lf", name, i, ce->values_gauge[i]);
450 } /* for (i) */
452 ce->last_time = vl->time;
453 ce->last_update = time (NULL);
454 ce->interval = vl->interval;
456 pthread_mutex_unlock (&cache_lock);
458 if (send_okay_notification == 0)
459 return (0);
461 /* Do not send okay notifications for uninteresting values, i. e. values for
462 * which no threshold is configured. */
463 status = ut_check_interesting (name);
464 if (status <= 0)
465 return (0);
467 /* Initialize the notification */
468 memset (&n, '\0', sizeof (n));
469 NOTIFICATION_INIT_VL (&n, vl, ds);
471 n.severity = NOTIF_OKAY;
472 n.time = vl->time;
474 ssnprintf (n.message, sizeof (n.message),
475 "Received a value for %s. It was missing for %u seconds.",
476 name, (unsigned int) update_delay);
478 plugin_dispatch_notification (&n);
480 return (0);
481 } /* int uc_update */
483 int uc_get_rate_by_name (const char *name, gauge_t **ret_values, size_t *ret_values_num)
484 {
485 gauge_t *ret = NULL;
486 size_t ret_num = 0;
487 cache_entry_t *ce = NULL;
488 int status = 0;
490 pthread_mutex_lock (&cache_lock);
492 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
493 {
494 assert (ce != NULL);
496 ret_num = ce->values_num;
497 ret = (gauge_t *) malloc (ret_num * sizeof (gauge_t));
498 if (ret == NULL)
499 {
500 ERROR ("utils_cache: uc_get_rate_by_name: malloc failed.");
501 status = -1;
502 }
503 else
504 {
505 memcpy (ret, ce->values_gauge, ret_num * sizeof (gauge_t));
506 }
507 }
508 else
509 {
510 DEBUG ("utils_cache: uc_get_rate_by_name: No such value: %s", name);
511 status = -1;
512 }
514 pthread_mutex_unlock (&cache_lock);
516 if (status == 0)
517 {
518 *ret_values = ret;
519 *ret_values_num = ret_num;
520 }
522 return (status);
523 } /* gauge_t *uc_get_rate_by_name */
525 gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
526 {
527 char name[6 * DATA_MAX_NAME_LEN];
528 gauge_t *ret = NULL;
529 size_t ret_num = 0;
530 int status;
532 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
533 {
534 ERROR ("utils_cache: uc_get_rate: FORMAT_VL failed.");
535 return (NULL);
536 }
538 status = uc_get_rate_by_name (name, &ret, &ret_num);
539 if (status != 0)
540 return (NULL);
542 /* This is important - the caller has no other way of knowing how many
543 * values are returned. */
544 if (ret_num != (size_t) ds->ds_num)
545 {
546 ERROR ("utils_cache: uc_get_rate: ds[%s] has %i values, "
547 "but uc_get_rate_by_name returned %zu.",
548 ds->type, ds->ds_num, ret_num);
549 sfree (ret);
550 return (NULL);
551 }
553 return (ret);
554 } /* gauge_t *uc_get_rate */
556 int uc_get_names (char ***ret_names, time_t **ret_times, size_t *ret_number)
557 {
558 c_avl_iterator_t *iter;
559 char *key;
560 cache_entry_t *value;
562 char **names = NULL;
563 time_t *times = NULL;
564 size_t number = 0;
566 int status = 0;
568 if ((ret_names == NULL) || (ret_number == NULL))
569 return (-1);
571 pthread_mutex_lock (&cache_lock);
573 iter = c_avl_get_iterator (cache_tree);
574 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
575 {
576 char **temp;
578 if (ret_times != NULL)
579 {
580 time_t *tmp_times;
582 tmp_times = (time_t *) realloc (times, sizeof (time_t) * (number + 1));
583 if (tmp_times == NULL)
584 {
585 status = -1;
586 break;
587 }
588 times = tmp_times;
589 times[number] = value->last_time;
590 }
592 temp = (char **) realloc (names, sizeof (char *) * (number + 1));
593 if (temp == NULL)
594 {
595 status = -1;
596 break;
597 }
598 names = temp;
599 names[number] = strdup (key);
600 if (names[number] == NULL)
601 {
602 status = -1;
603 break;
604 }
605 number++;
606 } /* while (c_avl_iterator_next) */
608 c_avl_iterator_destroy (iter);
609 pthread_mutex_unlock (&cache_lock);
611 if (status != 0)
612 {
613 size_t i;
615 for (i = 0; i < number; i++)
616 {
617 sfree (names[i]);
618 }
619 sfree (names);
621 return (-1);
622 }
624 *ret_names = names;
625 if (ret_times != NULL)
626 *ret_times = times;
627 *ret_number = number;
629 return (0);
630 } /* int uc_get_names */
632 int uc_get_state (const data_set_t *ds, const value_list_t *vl)
633 {
634 char name[6 * DATA_MAX_NAME_LEN];
635 cache_entry_t *ce = NULL;
636 int ret = STATE_ERROR;
638 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
639 {
640 ERROR ("uc_get_state: FORMAT_VL failed.");
641 return (STATE_ERROR);
642 }
644 pthread_mutex_lock (&cache_lock);
646 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
647 {
648 assert (ce != NULL);
649 ret = ce->state;
650 }
652 pthread_mutex_unlock (&cache_lock);
654 return (ret);
655 } /* int uc_get_state */
657 int uc_set_state (const data_set_t *ds, const value_list_t *vl, int state)
658 {
659 char name[6 * DATA_MAX_NAME_LEN];
660 cache_entry_t *ce = NULL;
661 int ret = -1;
663 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
664 {
665 ERROR ("uc_get_state: FORMAT_VL failed.");
666 return (STATE_ERROR);
667 }
669 pthread_mutex_lock (&cache_lock);
671 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
672 {
673 assert (ce != NULL);
674 ret = ce->state;
675 ce->state = state;
676 }
678 pthread_mutex_unlock (&cache_lock);
680 return (ret);
681 } /* int uc_set_state */
682 /* vim: set sw=2 ts=8 sts=2 tw=78 : */