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 ce = NULL;
300 status = c_avl_remove (cache_tree, keys[i],
301 (void *) &key, (void *) &ce);
302 if (status != 0)
303 {
304 ERROR ("uc_check_timeout: c_avl_remove (%s) failed.", keys[i]);
305 }
306 sfree (keys[i]);
307 sfree (key);
308 if (ce != NULL)
309 cache_free (ce);
310 continue;
311 }
313 /* If we get here, the value is ``interesting''. Query the record from the
314 * cache and update the state field. */
315 if (c_avl_get (cache_tree, keys[i], (void *) &ce) != 0)
316 {
317 ERROR ("uc_check_timeout: cannot get data for %s from cache", keys[i]);
318 /* Do not free `keys[i]' so a notification is sent further down. */
319 continue;
320 }
321 assert (ce != NULL);
323 if (status == 2) /* persist */
324 {
325 DEBUG ("uc_check_timeout: %s is missing, sending notification.",
326 keys[i]);
327 ce->state = STATE_MISSING;
328 /* Do not free `keys[i]' so a notification is sent further down. */
329 }
330 else if (status == 1) /* do not persist */
331 {
332 if (ce->state == STATE_MISSING)
333 {
334 DEBUG ("uc_check_timeout: %s is missing but "
335 "notification has already been sent.",
336 keys[i]);
337 /* Set `keys[i]' to NULL to no notification is sent. */
338 sfree (keys[i]);
339 }
340 else /* (ce->state != STATE_MISSING) */
341 {
342 DEBUG ("uc_check_timeout: %s is missing, sending one notification.",
343 keys[i]);
344 ce->state = STATE_MISSING;
345 /* Do not free `keys[i]' so a notification is sent further down. */
346 }
347 }
348 else
349 {
350 WARNING ("uc_check_timeout: ut_check_interesting (%s) returned "
351 "invalid status %i.",
352 keys[i], status);
353 sfree (keys[i]);
354 }
356 /* Make really sure the next iteration doesn't work with this pointer.
357 * There have been too many bugs in the past.. :/ -- octo */
358 ce = NULL;
359 } /* for (keys[i]) */
361 c_avl_iterator_destroy (iter);
363 pthread_mutex_unlock (&cache_lock);
365 for (i = 0; i < keys_len; i++)
366 {
367 if (keys[i] == NULL)
368 continue;
370 uc_send_notification (keys[i]);
371 sfree (keys[i]);
372 }
374 sfree (keys);
376 return (0);
377 } /* int uc_check_timeout */
379 int uc_update (const data_set_t *ds, const value_list_t *vl)
380 {
381 char name[6 * DATA_MAX_NAME_LEN];
382 cache_entry_t *ce = NULL;
383 int send_okay_notification = 0;
384 time_t update_delay = 0;
385 notification_t n;
386 int status;
387 int i;
389 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
390 {
391 ERROR ("uc_update: FORMAT_VL failed.");
392 return (-1);
393 }
395 pthread_mutex_lock (&cache_lock);
397 status = c_avl_get (cache_tree, name, (void *) &ce);
398 if (status != 0) /* entry does not yet exist */
399 {
400 status = uc_insert (ds, vl, name);
401 pthread_mutex_unlock (&cache_lock);
402 return (status);
403 }
405 assert (ce != NULL);
406 assert (ce->values_num == ds->ds_num);
408 if (ce->last_time >= vl->time)
409 {
410 pthread_mutex_unlock (&cache_lock);
411 NOTICE ("uc_update: Value too old: name = %s; value time = %u; "
412 "last cache update = %u;",
413 name, (unsigned int) vl->time, (unsigned int) ce->last_time);
414 return (-1);
415 }
417 /* Send a notification (after the lock has been released) if we switch the
418 * state from something else to `okay'. */
419 if (ce->state == STATE_MISSING)
420 {
421 send_okay_notification = 1;
422 ce->state = STATE_OKAY;
423 update_delay = time (NULL) - ce->last_update;
424 }
426 for (i = 0; i < ds->ds_num; i++)
427 {
428 if (ds->ds[i].type == DS_TYPE_COUNTER)
429 {
430 counter_t diff;
432 /* check if the counter has wrapped around */
433 if (vl->values[i].counter < ce->values_counter[i])
434 {
435 if (ce->values_counter[i] <= 4294967295U)
436 diff = (4294967295U - ce->values_counter[i])
437 + vl->values[i].counter;
438 else
439 diff = (18446744073709551615ULL - ce->values_counter[i])
440 + vl->values[i].counter;
441 }
442 else /* counter has NOT wrapped around */
443 {
444 diff = vl->values[i].counter - ce->values_counter[i];
445 }
447 ce->values_gauge[i] = ((double) diff)
448 / ((double) (vl->time - ce->last_time));
449 ce->values_counter[i] = vl->values[i].counter;
450 }
451 else /* if (ds->ds[i].type == DS_TYPE_GAUGE) */
452 {
453 ce->values_gauge[i] = vl->values[i].gauge;
454 }
455 DEBUG ("uc_update: %s: ds[%i] = %lf", name, i, ce->values_gauge[i]);
456 } /* for (i) */
458 ce->last_time = vl->time;
459 ce->last_update = time (NULL);
460 ce->interval = vl->interval;
462 pthread_mutex_unlock (&cache_lock);
464 if (send_okay_notification == 0)
465 return (0);
467 /* Do not send okay notifications for uninteresting values, i. e. values for
468 * which no threshold is configured. */
469 status = ut_check_interesting (name);
470 if (status <= 0)
471 return (0);
473 /* Initialize the notification */
474 memset (&n, '\0', sizeof (n));
475 NOTIFICATION_INIT_VL (&n, vl, ds);
477 n.severity = NOTIF_OKAY;
478 n.time = vl->time;
480 ssnprintf (n.message, sizeof (n.message),
481 "Received a value for %s. It was missing for %u seconds.",
482 name, (unsigned int) update_delay);
484 plugin_dispatch_notification (&n);
486 return (0);
487 } /* int uc_update */
489 int uc_get_rate_by_name (const char *name, gauge_t **ret_values, size_t *ret_values_num)
490 {
491 gauge_t *ret = NULL;
492 size_t ret_num = 0;
493 cache_entry_t *ce = NULL;
494 int status = 0;
496 pthread_mutex_lock (&cache_lock);
498 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
499 {
500 assert (ce != NULL);
502 ret_num = ce->values_num;
503 ret = (gauge_t *) malloc (ret_num * sizeof (gauge_t));
504 if (ret == NULL)
505 {
506 ERROR ("utils_cache: uc_get_rate_by_name: malloc failed.");
507 status = -1;
508 }
509 else
510 {
511 memcpy (ret, ce->values_gauge, ret_num * sizeof (gauge_t));
512 }
513 }
514 else
515 {
516 DEBUG ("utils_cache: uc_get_rate_by_name: No such value: %s", name);
517 status = -1;
518 }
520 pthread_mutex_unlock (&cache_lock);
522 if (status == 0)
523 {
524 *ret_values = ret;
525 *ret_values_num = ret_num;
526 }
528 return (status);
529 } /* gauge_t *uc_get_rate_by_name */
531 gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
532 {
533 char name[6 * DATA_MAX_NAME_LEN];
534 gauge_t *ret = NULL;
535 size_t ret_num = 0;
536 int status;
538 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
539 {
540 ERROR ("utils_cache: uc_get_rate: FORMAT_VL failed.");
541 return (NULL);
542 }
544 status = uc_get_rate_by_name (name, &ret, &ret_num);
545 if (status != 0)
546 return (NULL);
548 /* This is important - the caller has no other way of knowing how many
549 * values are returned. */
550 if (ret_num != (size_t) ds->ds_num)
551 {
552 ERROR ("utils_cache: uc_get_rate: ds[%s] has %i values, "
553 "but uc_get_rate_by_name returned %zu.",
554 ds->type, ds->ds_num, ret_num);
555 sfree (ret);
556 return (NULL);
557 }
559 return (ret);
560 } /* gauge_t *uc_get_rate */
562 int uc_get_names (char ***ret_names, time_t **ret_times, size_t *ret_number)
563 {
564 c_avl_iterator_t *iter;
565 char *key;
566 cache_entry_t *value;
568 char **names = NULL;
569 time_t *times = NULL;
570 size_t number = 0;
572 int status = 0;
574 if ((ret_names == NULL) || (ret_number == NULL))
575 return (-1);
577 pthread_mutex_lock (&cache_lock);
579 iter = c_avl_get_iterator (cache_tree);
580 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
581 {
582 char **temp;
584 if (ret_times != NULL)
585 {
586 time_t *tmp_times;
588 tmp_times = (time_t *) realloc (times, sizeof (time_t) * (number + 1));
589 if (tmp_times == NULL)
590 {
591 status = -1;
592 break;
593 }
594 times = tmp_times;
595 times[number] = value->last_time;
596 }
598 temp = (char **) realloc (names, sizeof (char *) * (number + 1));
599 if (temp == NULL)
600 {
601 status = -1;
602 break;
603 }
604 names = temp;
605 names[number] = strdup (key);
606 if (names[number] == NULL)
607 {
608 status = -1;
609 break;
610 }
611 number++;
612 } /* while (c_avl_iterator_next) */
614 c_avl_iterator_destroy (iter);
615 pthread_mutex_unlock (&cache_lock);
617 if (status != 0)
618 {
619 size_t i;
621 for (i = 0; i < number; i++)
622 {
623 sfree (names[i]);
624 }
625 sfree (names);
627 return (-1);
628 }
630 *ret_names = names;
631 if (ret_times != NULL)
632 *ret_times = times;
633 *ret_number = number;
635 return (0);
636 } /* int uc_get_names */
638 int uc_get_state (const data_set_t *ds, const value_list_t *vl)
639 {
640 char name[6 * DATA_MAX_NAME_LEN];
641 cache_entry_t *ce = NULL;
642 int ret = STATE_ERROR;
644 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
645 {
646 ERROR ("uc_get_state: FORMAT_VL failed.");
647 return (STATE_ERROR);
648 }
650 pthread_mutex_lock (&cache_lock);
652 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
653 {
654 assert (ce != NULL);
655 ret = ce->state;
656 }
658 pthread_mutex_unlock (&cache_lock);
660 return (ret);
661 } /* int uc_get_state */
663 int uc_set_state (const data_set_t *ds, const value_list_t *vl, int state)
664 {
665 char name[6 * DATA_MAX_NAME_LEN];
666 cache_entry_t *ce = NULL;
667 int ret = -1;
669 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
670 {
671 ERROR ("uc_get_state: FORMAT_VL failed.");
672 return (STATE_ERROR);
673 }
675 pthread_mutex_lock (&cache_lock);
677 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
678 {
679 assert (ce != NULL);
680 ret = ce->state;
681 ce->state = state;
682 }
684 pthread_mutex_unlock (&cache_lock);
686 return (ret);
687 } /* int uc_set_state */
688 /* vim: set sw=2 ts=8 sts=2 tw=78 : */