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 ERROR ("uc_insert: cache_alloc (%i) failed.", ds->ds_num);
190 return (-1);
191 }
193 sstrncpy (ce->name, key, sizeof (ce->name));
195 for (i = 0; i < ds->ds_num; i++)
196 {
197 if (ds->ds[i].type == DS_TYPE_COUNTER)
198 {
199 ce->values_gauge[i] = NAN;
200 ce->values_counter[i] = vl->values[i].counter;
201 }
202 else /* if (ds->ds[i].type == DS_TYPE_GAUGE) */
203 {
204 ce->values_gauge[i] = vl->values[i].gauge;
205 }
206 } /* for (i) */
208 ce->last_time = vl->time;
209 ce->last_update = time (NULL);
210 ce->interval = vl->interval;
211 ce->state = STATE_OKAY;
213 if (c_avl_insert (cache_tree, key_copy, ce) != 0)
214 {
215 sfree (key_copy);
216 ERROR ("uc_insert: c_avl_insert failed.");
217 return (-1);
218 }
220 DEBUG ("uc_insert: Added %s to the cache.", key);
221 return (0);
222 } /* int uc_insert */
224 int uc_init (void)
225 {
226 if (cache_tree == NULL)
227 cache_tree = c_avl_create ((int (*) (const void *, const void *))
228 cache_compare);
230 return (0);
231 } /* int uc_init */
233 int uc_check_timeout (void)
234 {
235 time_t now;
236 cache_entry_t *ce;
238 char **keys = NULL;
239 int keys_len = 0;
241 char *key;
242 c_avl_iterator_t *iter;
243 int i;
245 pthread_mutex_lock (&cache_lock);
247 now = time (NULL);
249 /* Build a list of entries to be flushed */
250 iter = c_avl_get_iterator (cache_tree);
251 while (c_avl_iterator_next (iter, (void *) &key, (void *) &ce) == 0)
252 {
253 /* If entry has not been updated, add to `keys' array */
254 if ((now - ce->last_update) >= (2 * ce->interval))
255 {
256 char **tmp;
258 tmp = (char **) realloc ((void *) keys,
259 (keys_len + 1) * sizeof (char *));
260 if (tmp == NULL)
261 {
262 ERROR ("uc_purge: realloc failed.");
263 c_avl_iterator_destroy (iter);
264 return (-1);
265 }
267 keys = tmp;
268 keys[keys_len] = strdup (key);
269 if (keys[keys_len] == NULL)
270 {
271 ERROR ("uc_check_timeout: strdup failed.");
272 continue;
273 }
274 keys_len++;
275 }
276 } /* while (c_avl_iterator_next) */
278 for (i = 0; i < keys_len; i++)
279 {
280 int status;
282 status = ut_check_interesting (keys[i]);
284 if (status < 0)
285 {
286 ERROR ("uc_check_timeout: ut_check_interesting failed.");
287 sfree (keys[i]);
288 }
289 else if (status == 0) /* ``service'' is uninteresting */
290 {
291 ce = NULL;
292 DEBUG ("uc_check_timeout: %s is missing but ``uninteresting''",
293 keys[i]);
294 status = c_avl_remove (cache_tree, keys[i],
295 (void *) &key, (void *) &ce);
296 if (status != 0)
297 {
298 ERROR ("uc_check_timeout: c_avl_remove (%s) failed.", keys[i]);
299 }
300 sfree (keys[i]);
301 sfree (key);
302 cache_free (ce);
303 }
304 else if (status == 1) /* persist */
305 {
306 DEBUG ("uc_check_timeout: %s is missing, sending notification.",
307 keys[i]);
308 ce->state = STATE_MISSING;
309 }
310 else if (status == 2) /* do not persist */
311 {
312 if (ce->state == STATE_MISSING)
313 {
314 DEBUG ("uc_check_timeout: %s is missing but "
315 "notification has already been sent.",
316 keys[i]);
317 sfree (keys[i]);
318 }
319 else /* (ce->state != STATE_MISSING) */
320 {
321 DEBUG ("uc_check_timeout: %s is missing, sending one notification.",
322 keys[i]);
323 ce->state = STATE_MISSING;
324 }
325 }
326 else
327 {
328 WARNING ("uc_check_timeout: ut_check_interesting (%s) returned "
329 "invalid status %i.",
330 keys[i], status);
331 }
332 } /* for (keys[i]) */
334 c_avl_iterator_destroy (iter);
336 pthread_mutex_unlock (&cache_lock);
338 for (i = 0; i < keys_len; i++)
339 {
340 if (keys[i] == NULL)
341 continue;
343 uc_send_notification (keys[i]);
344 sfree (keys[i]);
345 }
347 sfree (keys);
349 return (0);
350 } /* int uc_check_timeout */
352 int uc_update (const data_set_t *ds, const value_list_t *vl)
353 {
354 char name[6 * DATA_MAX_NAME_LEN];
355 cache_entry_t *ce = NULL;
356 int send_okay_notification = 0;
357 time_t update_delay = 0;
358 notification_t n;
359 int status;
360 int i;
362 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
363 {
364 ERROR ("uc_update: FORMAT_VL failed.");
365 return (-1);
366 }
368 pthread_mutex_lock (&cache_lock);
370 status = c_avl_get (cache_tree, name, (void *) &ce);
371 if (status != 0) /* entry does not yet exist */
372 {
373 status = uc_insert (ds, vl, name);
374 pthread_mutex_unlock (&cache_lock);
375 return (status);
376 }
378 assert (ce != NULL);
379 assert (ce->values_num == ds->ds_num);
381 if (ce->last_time >= vl->time)
382 {
383 pthread_mutex_unlock (&cache_lock);
384 NOTICE ("uc_update: Value too old: name = %s; value time = %u; "
385 "last cache update = %u;",
386 name, (unsigned int) vl->time, (unsigned int) ce->last_time);
387 return (-1);
388 }
390 /* Send a notification (after the lock has been released) if we switch the
391 * state from something else to `okay'. */
392 if (ce->state == STATE_MISSING)
393 {
394 send_okay_notification = 1;
395 ce->state = STATE_OKAY;
396 update_delay = time (NULL) - ce->last_update;
397 }
399 for (i = 0; i < ds->ds_num; i++)
400 {
401 if (ds->ds[i].type == DS_TYPE_COUNTER)
402 {
403 counter_t diff;
405 /* check if the counter has wrapped around */
406 if (vl->values[i].counter < ce->values_counter[i])
407 {
408 if (ce->values_counter[i] <= 4294967295U)
409 diff = (4294967295U - ce->values_counter[i])
410 + vl->values[i].counter;
411 else
412 diff = (18446744073709551615ULL - ce->values_counter[i])
413 + vl->values[i].counter;
414 }
415 else /* counter has NOT wrapped around */
416 {
417 diff = vl->values[i].counter - ce->values_counter[i];
418 }
420 ce->values_gauge[i] = ((double) diff)
421 / ((double) (vl->time - ce->last_time));
422 ce->values_counter[i] = vl->values[i].counter;
423 }
424 else /* if (ds->ds[i].type == DS_TYPE_GAUGE) */
425 {
426 ce->values_gauge[i] = vl->values[i].gauge;
427 }
428 DEBUG ("uc_update: %s: ds[%i] = %lf", name, i, ce->values_gauge[i]);
429 } /* for (i) */
431 ce->last_time = vl->time;
432 ce->last_update = time (NULL);
433 ce->interval = vl->interval;
435 pthread_mutex_unlock (&cache_lock);
437 if (send_okay_notification == 0)
438 return (0);
440 /* Do not send okay notifications for uninteresting values, i. e. values for
441 * which no threshold is configured. */
442 status = ut_check_interesting (name);
443 if (status <= 0)
444 return (0);
446 /* Initialize the notification */
447 memset (&n, '\0', sizeof (n));
448 NOTIFICATION_INIT_VL (&n, vl, ds);
450 n.severity = NOTIF_OKAY;
451 n.time = vl->time;
453 ssnprintf (n.message, sizeof (n.message),
454 "Received a value for %s. It was missing for %u seconds.",
455 name, (unsigned int) update_delay);
457 plugin_dispatch_notification (&n);
459 return (0);
460 } /* int uc_update */
462 int uc_get_rate_by_name (const char *name, gauge_t **ret_values, size_t *ret_values_num)
463 {
464 gauge_t *ret = NULL;
465 size_t ret_num = 0;
466 cache_entry_t *ce = NULL;
467 int status = 0;
469 pthread_mutex_lock (&cache_lock);
471 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
472 {
473 assert (ce != NULL);
475 ret_num = ce->values_num;
476 ret = (gauge_t *) malloc (ret_num * sizeof (gauge_t));
477 if (ret == NULL)
478 {
479 ERROR ("utils_cache: uc_get_rate_by_name: malloc failed.");
480 status = -1;
481 }
482 else
483 {
484 memcpy (ret, ce->values_gauge, ret_num * sizeof (gauge_t));
485 }
486 }
487 else
488 {
489 DEBUG ("utils_cache: uc_get_rate_by_name: No such value: %s", name);
490 status = -1;
491 }
493 pthread_mutex_unlock (&cache_lock);
495 if (status == 0)
496 {
497 *ret_values = ret;
498 *ret_values_num = ret_num;
499 }
501 return (status);
502 } /* gauge_t *uc_get_rate_by_name */
504 gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
505 {
506 char name[6 * DATA_MAX_NAME_LEN];
507 gauge_t *ret = NULL;
508 size_t ret_num = 0;
509 int status;
511 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
512 {
513 ERROR ("uc_insert: FORMAT_VL failed.");
514 return (NULL);
515 }
517 status = uc_get_rate_by_name (name, &ret, &ret_num);
518 if (status != 0)
519 return (NULL);
521 /* This is important - the caller has no other way of knowing how many
522 * values are returned. */
523 if (ret_num != ds->ds_num)
524 {
525 ERROR ("utils_cache: uc_get_rate: ds[%s] has %i values, "
526 "but uc_get_rate_by_name returned %zu.",
527 ds->type, ds->ds_num, ret_num);
528 sfree (ret);
529 return (NULL);
530 }
532 return (ret);
533 } /* gauge_t *uc_get_rate */
535 int uc_get_names (char ***ret_names, time_t **ret_times, size_t *ret_number)
536 {
537 c_avl_iterator_t *iter;
538 char *key;
539 cache_entry_t *value;
541 char **names = NULL;
542 time_t *times = NULL;
543 size_t number = 0;
545 int status = 0;
547 if ((ret_names == NULL) || (ret_number == NULL))
548 return (-1);
550 pthread_mutex_lock (&cache_lock);
552 iter = c_avl_get_iterator (cache_tree);
553 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
554 {
555 char **temp;
557 if (ret_times != NULL)
558 {
559 time_t *tmp_times;
561 tmp_times = (time_t *) realloc (times, sizeof (time_t) * (number + 1));
562 if (tmp_times == NULL)
563 {
564 status = -1;
565 break;
566 }
567 times = tmp_times;
568 times[number] = value->last_time;
569 }
571 temp = (char **) realloc (names, sizeof (char *) * (number + 1));
572 if (temp == NULL)
573 {
574 status = -1;
575 break;
576 }
577 names = temp;
578 names[number] = strdup (key);
579 if (names[number] == NULL)
580 {
581 status = -1;
582 break;
583 }
584 number++;
585 } /* while (c_avl_iterator_next) */
587 c_avl_iterator_destroy (iter);
588 pthread_mutex_unlock (&cache_lock);
590 if (status != 0)
591 {
592 size_t i;
594 for (i = 0; i < number; i++)
595 {
596 sfree (names[i]);
597 }
598 sfree (names);
600 return (-1);
601 }
603 *ret_names = names;
604 if (ret_times != NULL)
605 *ret_times = times;
606 *ret_number = number;
608 return (0);
609 } /* int uc_get_names */
611 int uc_get_state (const data_set_t *ds, const value_list_t *vl)
612 {
613 char name[6 * DATA_MAX_NAME_LEN];
614 cache_entry_t *ce = NULL;
615 int ret = STATE_ERROR;
617 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
618 {
619 ERROR ("uc_get_state: FORMAT_VL failed.");
620 return (STATE_ERROR);
621 }
623 pthread_mutex_lock (&cache_lock);
625 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
626 {
627 assert (ce != NULL);
628 ret = ce->state;
629 }
631 pthread_mutex_unlock (&cache_lock);
633 return (ret);
634 } /* int uc_get_state */
636 int uc_set_state (const data_set_t *ds, const value_list_t *vl, int state)
637 {
638 char name[6 * DATA_MAX_NAME_LEN];
639 cache_entry_t *ce = NULL;
640 int ret = -1;
642 if (FORMAT_VL (name, sizeof (name), vl, ds) != 0)
643 {
644 ERROR ("uc_get_state: FORMAT_VL failed.");
645 return (STATE_ERROR);
646 }
648 pthread_mutex_lock (&cache_lock);
650 if (c_avl_get (cache_tree, name, (void *) &ce) == 0)
651 {
652 assert (ce != NULL);
653 ret = ce->state;
654 ce->state = state;
655 }
657 pthread_mutex_unlock (&cache_lock);
659 return (ret);
660 } /* int uc_set_state */
661 /* vim: set sw=2 ts=8 sts=2 tw=78 : */