1 /**
2 * collectd - src/plugin.c
3 * Copyright (C) 2005-2013 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 collectd.org>
20 * Sebastian Harl <sh at tokkee.org>
21 **/
23 #include "collectd.h"
24 #include "common.h"
25 #include "plugin.h"
26 #include "configfile.h"
27 #include "filter_chain.h"
28 #include "utils_avltree.h"
29 #include "utils_cache.h"
30 #include "utils_complain.h"
31 #include "utils_llist.h"
32 #include "utils_heap.h"
33 #include "utils_time.h"
34 #include "utils_random.h"
36 #if HAVE_PTHREAD_H
37 # include <pthread.h>
38 #endif
40 #include <ltdl.h>
42 /*
43 * Private structures
44 */
45 struct callback_func_s
46 {
47 void *cf_callback;
48 user_data_t cf_udata;
49 plugin_ctx_t cf_ctx;
50 };
51 typedef struct callback_func_s callback_func_t;
53 #define RF_SIMPLE 0
54 #define RF_COMPLEX 1
55 #define RF_REMOVE 65535
56 struct read_func_s
57 {
58 /* `read_func_t' "inherits" from `callback_func_t'.
59 * The `rf_super' member MUST be the first one in this structure! */
60 #define rf_callback rf_super.cf_callback
61 #define rf_udata rf_super.cf_udata
62 #define rf_ctx rf_super.cf_ctx
63 callback_func_t rf_super;
64 char rf_group[DATA_MAX_NAME_LEN];
65 char *rf_name;
66 int rf_type;
67 cdtime_t rf_interval;
68 cdtime_t rf_effective_interval;
69 cdtime_t rf_next_read;
70 };
71 typedef struct read_func_s read_func_t;
73 struct write_queue_s;
74 typedef struct write_queue_s write_queue_t;
75 struct write_queue_s
76 {
77 value_list_t *vl;
78 plugin_ctx_t ctx;
79 write_queue_t *next;
80 };
82 /*
83 * Private variables
84 */
85 static c_avl_tree_t *plugins_loaded = NULL;
87 static llist_t *list_init;
88 static llist_t *list_write;
89 static llist_t *list_flush;
90 static llist_t *list_missing;
91 static llist_t *list_shutdown;
92 static llist_t *list_log;
93 static llist_t *list_notification;
95 static fc_chain_t *pre_cache_chain = NULL;
96 static fc_chain_t *post_cache_chain = NULL;
98 static c_avl_tree_t *data_sets;
100 static char *plugindir = NULL;
102 static c_heap_t *read_heap = NULL;
103 static llist_t *read_list;
104 static int read_loop = 1;
105 static pthread_mutex_t read_lock = PTHREAD_MUTEX_INITIALIZER;
106 static pthread_cond_t read_cond = PTHREAD_COND_INITIALIZER;
107 static pthread_t *read_threads = NULL;
108 static int read_threads_num = 0;
110 static write_queue_t *write_queue_head;
111 static write_queue_t *write_queue_tail;
112 static long write_queue_length = 0;
113 static _Bool write_loop = 1;
114 static pthread_mutex_t write_lock = PTHREAD_MUTEX_INITIALIZER;
115 static pthread_cond_t write_cond = PTHREAD_COND_INITIALIZER;
116 static pthread_t *write_threads = NULL;
117 static size_t write_threads_num = 0;
119 static pthread_key_t plugin_ctx_key;
120 static _Bool plugin_ctx_key_initialized = 0;
122 static long write_limit_high = 0;
123 static long write_limit_low = 0;
124 cdtime_t last_drop_time = 0;
126 /*
127 * Static functions
128 */
129 static int plugin_dispatch_values_internal (value_list_t *vl);
131 static const char *plugin_get_dir (void)
132 {
133 if (plugindir == NULL)
134 return (PLUGINDIR);
135 else
136 return (plugindir);
137 }
139 static void destroy_callback (callback_func_t *cf) /* {{{ */
140 {
141 if (cf == NULL)
142 return;
144 if ((cf->cf_udata.data != NULL) && (cf->cf_udata.free_func != NULL))
145 {
146 cf->cf_udata.free_func (cf->cf_udata.data);
147 cf->cf_udata.data = NULL;
148 cf->cf_udata.free_func = NULL;
149 }
150 sfree (cf);
151 } /* }}} void destroy_callback */
153 static void destroy_all_callbacks (llist_t **list) /* {{{ */
154 {
155 llentry_t *le;
157 if (*list == NULL)
158 return;
160 le = llist_head (*list);
161 while (le != NULL)
162 {
163 llentry_t *le_next;
165 le_next = le->next;
167 sfree (le->key);
168 destroy_callback (le->value);
169 le->value = NULL;
171 le = le_next;
172 }
174 llist_destroy (*list);
175 *list = NULL;
176 } /* }}} void destroy_all_callbacks */
178 static void destroy_read_heap (void) /* {{{ */
179 {
180 if (read_heap == NULL)
181 return;
183 while (42)
184 {
185 callback_func_t *cf;
187 cf = c_heap_get_root (read_heap);
188 if (cf == NULL)
189 break;
191 destroy_callback (cf);
192 }
194 c_heap_destroy (read_heap);
195 read_heap = NULL;
196 } /* }}} void destroy_read_heap */
198 static int register_callback (llist_t **list, /* {{{ */
199 const char *name, callback_func_t *cf)
200 {
201 llentry_t *le;
202 char *key;
204 if (*list == NULL)
205 {
206 *list = llist_create ();
207 if (*list == NULL)
208 {
209 ERROR ("plugin: register_callback: "
210 "llist_create failed.");
211 destroy_callback (cf);
212 return (-1);
213 }
214 }
216 key = strdup (name);
217 if (key == NULL)
218 {
219 ERROR ("plugin: register_callback: strdup failed.");
220 destroy_callback (cf);
221 return (-1);
222 }
224 le = llist_search (*list, name);
225 if (le == NULL)
226 {
227 le = llentry_create (key, cf);
228 if (le == NULL)
229 {
230 ERROR ("plugin: register_callback: "
231 "llentry_create failed.");
232 free (key);
233 destroy_callback (cf);
234 return (-1);
235 }
237 llist_append (*list, le);
238 }
239 else
240 {
241 callback_func_t *old_cf;
243 old_cf = le->value;
244 le->value = cf;
246 WARNING ("plugin: register_callback: "
247 "a callback named `%s' already exists - "
248 "overwriting the old entry!", name);
250 destroy_callback (old_cf);
251 sfree (key);
252 }
254 return (0);
255 } /* }}} int register_callback */
257 static int create_register_callback (llist_t **list, /* {{{ */
258 const char *name, void *callback, user_data_t *ud)
259 {
260 callback_func_t *cf;
262 cf = (callback_func_t *) malloc (sizeof (*cf));
263 if (cf == NULL)
264 {
265 ERROR ("plugin: create_register_callback: malloc failed.");
266 return (-1);
267 }
268 memset (cf, 0, sizeof (*cf));
270 cf->cf_callback = callback;
271 if (ud == NULL)
272 {
273 cf->cf_udata.data = NULL;
274 cf->cf_udata.free_func = NULL;
275 }
276 else
277 {
278 cf->cf_udata = *ud;
279 }
281 cf->cf_ctx = plugin_get_ctx ();
283 return (register_callback (list, name, cf));
284 } /* }}} int create_register_callback */
286 static int plugin_unregister (llist_t *list, const char *name) /* {{{ */
287 {
288 llentry_t *e;
290 if (list == NULL)
291 return (-1);
293 e = llist_search (list, name);
294 if (e == NULL)
295 return (-1);
297 llist_remove (list, e);
299 sfree (e->key);
300 destroy_callback (e->value);
302 llentry_destroy (e);
304 return (0);
305 } /* }}} int plugin_unregister */
307 /*
308 * (Try to) load the shared object `file'. Won't complain if it isn't a shared
309 * object, but it will bitch about a shared object not having a
310 * ``module_register'' symbol..
311 */
312 static int plugin_load_file (char *file, uint32_t flags)
313 {
314 lt_dlhandle dlh;
315 void (*reg_handle) (void);
317 lt_dlinit ();
318 lt_dlerror (); /* clear errors */
320 #if LIBTOOL_VERSION == 2
321 if (flags & PLUGIN_FLAGS_GLOBAL) {
322 lt_dladvise advise;
323 lt_dladvise_init(&advise);
324 lt_dladvise_global(&advise);
325 dlh = lt_dlopenadvise(file, advise);
326 lt_dladvise_destroy(&advise);
327 } else {
328 dlh = lt_dlopen (file);
329 }
330 #else /* if LIBTOOL_VERSION == 1 */
331 if (flags & PLUGIN_FLAGS_GLOBAL)
332 WARNING ("plugin_load_file: The global flag is not supported, "
333 "libtool 2 is required for this.");
334 dlh = lt_dlopen (file);
335 #endif
337 if (dlh == NULL)
338 {
339 char errbuf[1024] = "";
341 ssnprintf (errbuf, sizeof (errbuf),
342 "lt_dlopen (\"%s\") failed: %s. "
343 "The most common cause for this problem are "
344 "missing dependencies. Use ldd(1) to check "
345 "the dependencies of the plugin "
346 "/ shared object.",
347 file, lt_dlerror ());
349 ERROR ("%s", errbuf);
350 /* Make sure this is printed to STDERR in any case, but also
351 * make sure it's printed only once. */
352 if (list_log != NULL)
353 fprintf (stderr, "ERROR: %s\n", errbuf);
355 return (1);
356 }
358 if ((reg_handle = (void (*) (void)) lt_dlsym (dlh, "module_register")) == NULL)
359 {
360 WARNING ("Couldn't find symbol \"module_register\" in \"%s\": %s\n",
361 file, lt_dlerror ());
362 lt_dlclose (dlh);
363 return (-1);
364 }
366 (*reg_handle) ();
368 return (0);
369 }
371 static void *plugin_read_thread (void __attribute__((unused)) *args)
372 {
373 while (read_loop != 0)
374 {
375 read_func_t *rf;
376 plugin_ctx_t old_ctx;
377 cdtime_t now;
378 int status;
379 int rf_type;
380 int rc;
382 /* Get the read function that needs to be read next.
383 * We don't need to hold "read_lock" for the heap, but we need
384 * to call c_heap_get_root() and pthread_cond_wait() in the
385 * same protected block. */
386 pthread_mutex_lock (&read_lock);
387 rf = c_heap_get_root (read_heap);
388 if (rf == NULL)
389 {
390 pthread_cond_wait (&read_cond, &read_lock);
391 pthread_mutex_unlock (&read_lock);
392 continue;
393 }
394 pthread_mutex_unlock (&read_lock);
396 if (rf->rf_interval == 0)
397 {
398 /* this should not happen, because the interval is set
399 * for each plugin when loading it
400 * XXX: issue a warning? */
401 rf->rf_interval = plugin_get_interval ();
402 rf->rf_effective_interval = rf->rf_interval;
404 rf->rf_next_read = cdtime ();
405 }
407 /* sleep until this entry is due,
408 * using pthread_cond_timedwait */
409 pthread_mutex_lock (&read_lock);
410 /* In pthread_cond_timedwait, spurious wakeups are possible
411 * (and really happen, at least on NetBSD with > 1 CPU), thus
412 * we need to re-evaluate the condition every time
413 * pthread_cond_timedwait returns. */
414 rc = 0;
415 while ((read_loop != 0)
416 && (cdtime () < rf->rf_next_read)
417 && rc == 0)
418 {
419 struct timespec ts = { 0 };
421 CDTIME_T_TO_TIMESPEC (rf->rf_next_read, &ts);
423 rc = pthread_cond_timedwait (&read_cond, &read_lock,
424 &ts);
425 }
427 /* Must hold `read_lock' when accessing `rf->rf_type'. */
428 rf_type = rf->rf_type;
429 pthread_mutex_unlock (&read_lock);
431 /* Check if we're supposed to stop.. This may have interrupted
432 * the sleep, too. */
433 if (read_loop == 0)
434 {
435 /* Insert `rf' again, so it can be free'd correctly */
436 c_heap_insert (read_heap, rf);
437 break;
438 }
440 /* The entry has been marked for deletion. The linked list
441 * entry has already been removed by `plugin_unregister_read'.
442 * All we have to do here is free the `read_func_t' and
443 * continue. */
444 if (rf_type == RF_REMOVE)
445 {
446 DEBUG ("plugin_read_thread: Destroying the `%s' "
447 "callback.", rf->rf_name);
448 sfree (rf->rf_name);
449 destroy_callback ((callback_func_t *) rf);
450 rf = NULL;
451 continue;
452 }
454 DEBUG ("plugin_read_thread: Handling `%s'.", rf->rf_name);
456 old_ctx = plugin_set_ctx (rf->rf_ctx);
458 if (rf_type == RF_SIMPLE)
459 {
460 int (*callback) (void);
462 callback = rf->rf_callback;
463 status = (*callback) ();
464 }
465 else
466 {
467 plugin_read_cb callback;
469 assert (rf_type == RF_COMPLEX);
471 callback = rf->rf_callback;
472 status = (*callback) (&rf->rf_udata);
473 }
475 plugin_set_ctx (old_ctx);
477 /* If the function signals failure, we will increase the
478 * intervals in which it will be called. */
479 if (status != 0)
480 {
481 rf->rf_effective_interval *= 2;
482 if (rf->rf_effective_interval > TIME_T_TO_CDTIME_T (86400))
483 rf->rf_effective_interval = TIME_T_TO_CDTIME_T (86400);
485 NOTICE ("read-function of plugin `%s' failed. "
486 "Will suspend it for %.3f seconds.",
487 rf->rf_name,
488 CDTIME_T_TO_DOUBLE (rf->rf_effective_interval));
489 }
490 else
491 {
492 /* Success: Restore the interval, if it was changed. */
493 rf->rf_effective_interval = rf->rf_interval;
494 }
496 /* update the ``next read due'' field */
497 now = cdtime ();
499 DEBUG ("plugin_read_thread: Effective interval of the "
500 "%s plugin is %.3f seconds.",
501 rf->rf_name,
502 CDTIME_T_TO_DOUBLE (rf->rf_effective_interval));
504 /* Calculate the next (absolute) time at which this function
505 * should be called. */
506 rf->rf_next_read += rf->rf_effective_interval;
508 /* Check, if `rf_next_read' is in the past. */
509 if (rf->rf_next_read < now)
510 {
511 /* `rf_next_read' is in the past. Insert `now'
512 * so this value doesn't trail off into the
513 * past too much. */
514 rf->rf_next_read = now;
515 }
517 DEBUG ("plugin_read_thread: Next read of the %s plugin at %.3f.",
518 rf->rf_name,
519 CDTIME_T_TO_DOUBLE (rf->rf_next_read));
521 /* Re-insert this read function into the heap again. */
522 c_heap_insert (read_heap, rf);
523 } /* while (read_loop) */
525 pthread_exit (NULL);
526 return ((void *) 0);
527 } /* void *plugin_read_thread */
529 static void start_read_threads (int num)
530 {
531 int i;
533 if (read_threads != NULL)
534 return;
536 read_threads = (pthread_t *) calloc (num, sizeof (pthread_t));
537 if (read_threads == NULL)
538 {
539 ERROR ("plugin: start_read_threads: calloc failed.");
540 return;
541 }
543 read_threads_num = 0;
544 for (i = 0; i < num; i++)
545 {
546 if (pthread_create (read_threads + read_threads_num, NULL,
547 plugin_read_thread, NULL) == 0)
548 {
549 read_threads_num++;
550 }
551 else
552 {
553 ERROR ("plugin: start_read_threads: pthread_create failed.");
554 return;
555 }
556 } /* for (i) */
557 } /* void start_read_threads */
559 static void stop_read_threads (void)
560 {
561 int i;
563 if (read_threads == NULL)
564 return;
566 INFO ("collectd: Stopping %i read threads.", read_threads_num);
568 pthread_mutex_lock (&read_lock);
569 read_loop = 0;
570 DEBUG ("plugin: stop_read_threads: Signalling `read_cond'");
571 pthread_cond_broadcast (&read_cond);
572 pthread_mutex_unlock (&read_lock);
574 for (i = 0; i < read_threads_num; i++)
575 {
576 if (pthread_join (read_threads[i], NULL) != 0)
577 {
578 ERROR ("plugin: stop_read_threads: pthread_join failed.");
579 }
580 read_threads[i] = (pthread_t) 0;
581 }
582 sfree (read_threads);
583 read_threads_num = 0;
584 } /* void stop_read_threads */
586 static void plugin_value_list_free (value_list_t *vl) /* {{{ */
587 {
588 if (vl == NULL)
589 return;
591 meta_data_destroy (vl->meta);
592 sfree (vl->values);
593 sfree (vl);
594 } /* }}} void plugin_value_list_free */
596 static value_list_t *plugin_value_list_clone (value_list_t const *vl_orig) /* {{{ */
597 {
598 value_list_t *vl;
600 if (vl_orig == NULL)
601 return (NULL);
603 vl = malloc (sizeof (*vl));
604 if (vl == NULL)
605 return (NULL);
606 memcpy (vl, vl_orig, sizeof (*vl));
608 vl->values = calloc (vl_orig->values_len, sizeof (*vl->values));
609 if (vl->values == NULL)
610 {
611 plugin_value_list_free (vl);
612 return (NULL);
613 }
614 memcpy (vl->values, vl_orig->values,
615 vl_orig->values_len * sizeof (*vl->values));
617 vl->meta = meta_data_clone (vl->meta);
618 if ((vl_orig->meta != NULL) && (vl->meta == NULL))
619 {
620 plugin_value_list_free (vl);
621 return (NULL);
622 }
624 if (vl->time == 0)
625 vl->time = cdtime ();
627 /* Fill in the interval from the thread context, if it is zero. */
628 if (vl->interval == 0)
629 {
630 plugin_ctx_t ctx = plugin_get_ctx ();
632 if (ctx.interval != 0)
633 vl->interval = ctx.interval;
634 else
635 {
636 char name[6 * DATA_MAX_NAME_LEN];
637 FORMAT_VL (name, sizeof (name), vl);
638 ERROR ("plugin_value_list_clone: Unable to determine "
639 "interval from context for "
640 "value list \"%s\". "
641 "This indicates a broken plugin. "
642 "Please report this problem to the "
643 "collectd mailing list or at "
644 "<http://collectd.org/bugs/>.", name);
645 vl->interval = cf_get_default_interval ();
646 }
647 }
649 return (vl);
650 } /* }}} value_list_t *plugin_value_list_clone */
652 static int plugin_write_enqueue (value_list_t const *vl) /* {{{ */
653 {
654 write_queue_t *q;
656 q = malloc (sizeof (*q));
657 if (q == NULL)
658 return (ENOMEM);
659 q->next = NULL;
661 q->vl = plugin_value_list_clone (vl);
662 if (q->vl == NULL)
663 {
664 sfree (q);
665 return (ENOMEM);
666 }
668 /* Store context of caller (read plugin); otherwise, it would not be
669 * available to the write plugins when actually dispatching the
670 * value-list later on. */
671 q->ctx = plugin_get_ctx ();
673 pthread_mutex_lock (&write_lock);
675 if (write_queue_tail == NULL)
676 {
677 write_queue_head = q;
678 write_queue_tail = q;
679 write_queue_length = 1;
680 }
681 else
682 {
683 write_queue_tail->next = q;
684 write_queue_tail = q;
685 write_queue_length += 1;
686 }
688 pthread_cond_signal (&write_cond);
689 pthread_mutex_unlock (&write_lock);
691 return (0);
692 } /* }}} int plugin_write_enqueue */
694 static value_list_t *plugin_write_dequeue (void) /* {{{ */
695 {
696 write_queue_t *q;
697 value_list_t *vl;
699 pthread_mutex_lock (&write_lock);
701 while (write_loop && (write_queue_head == NULL))
702 pthread_cond_wait (&write_cond, &write_lock);
704 if (write_queue_head == NULL)
705 {
706 pthread_mutex_unlock (&write_lock);
707 return (NULL);
708 }
710 q = write_queue_head;
711 write_queue_head = q->next;
712 write_queue_length -= 1;
713 if (write_queue_head == NULL) {
714 write_queue_tail = NULL;
715 assert(0 == write_queue_length);
716 }
718 pthread_mutex_unlock (&write_lock);
720 (void) plugin_set_ctx (q->ctx);
722 vl = q->vl;
723 sfree (q);
724 return (vl);
725 } /* }}} value_list_t *plugin_write_dequeue */
727 static void *plugin_write_thread (void __attribute__((unused)) *args) /* {{{ */
728 {
729 while (write_loop)
730 {
731 value_list_t *vl = plugin_write_dequeue ();
732 if (vl == NULL)
733 continue;
735 plugin_dispatch_values_internal (vl);
737 plugin_value_list_free (vl);
738 }
740 pthread_exit (NULL);
741 return ((void *) 0);
742 } /* }}} void *plugin_write_thread */
744 static void start_write_threads (size_t num) /* {{{ */
745 {
746 size_t i;
748 if (write_threads != NULL)
749 return;
751 write_threads = (pthread_t *) calloc (num, sizeof (pthread_t));
752 if (write_threads == NULL)
753 {
754 ERROR ("plugin: start_write_threads: calloc failed.");
755 return;
756 }
758 write_threads_num = 0;
759 for (i = 0; i < num; i++)
760 {
761 int status;
763 status = pthread_create (write_threads + write_threads_num,
764 /* attr = */ NULL,
765 plugin_write_thread,
766 /* arg = */ NULL);
767 if (status != 0)
768 {
769 char errbuf[1024];
770 ERROR ("plugin: start_write_threads: pthread_create failed "
771 "with status %i (%s).", status,
772 sstrerror (status, errbuf, sizeof (errbuf)));
773 return;
774 }
776 write_threads_num++;
777 } /* for (i) */
778 } /* }}} void start_write_threads */
780 static void stop_write_threads (void) /* {{{ */
781 {
782 write_queue_t *q;
783 int i;
785 if (write_threads == NULL)
786 return;
788 INFO ("collectd: Stopping %zu write threads.", write_threads_num);
790 pthread_mutex_lock (&write_lock);
791 write_loop = 0;
792 DEBUG ("plugin: stop_write_threads: Signalling `write_cond'");
793 pthread_cond_broadcast (&write_cond);
794 pthread_mutex_unlock (&write_lock);
796 for (i = 0; i < write_threads_num; i++)
797 {
798 if (pthread_join (write_threads[i], NULL) != 0)
799 {
800 ERROR ("plugin: stop_write_threads: pthread_join failed.");
801 }
802 write_threads[i] = (pthread_t) 0;
803 }
804 sfree (write_threads);
805 write_threads_num = 0;
807 pthread_mutex_lock (&write_lock);
808 i = 0;
809 for (q = write_queue_head; q != NULL; )
810 {
811 write_queue_t *q1 = q;
812 plugin_value_list_free (q->vl);
813 q = q->next;
814 sfree (q1);
815 i++;
816 }
817 write_queue_head = NULL;
818 write_queue_tail = NULL;
819 write_queue_length = 0;
820 pthread_mutex_unlock (&write_lock);
822 if (i > 0)
823 {
824 WARNING ("plugin: %i value list%s left after shutting down "
825 "the write threads.",
826 i, (i == 1) ? " was" : "s were");
827 }
828 } /* }}} void stop_write_threads */
830 /*
831 * Public functions
832 */
833 void plugin_set_dir (const char *dir)
834 {
835 if (plugindir != NULL)
836 free (plugindir);
838 if (dir == NULL)
839 plugindir = NULL;
840 else if ((plugindir = strdup (dir)) == NULL)
841 {
842 char errbuf[1024];
843 ERROR ("strdup failed: %s",
844 sstrerror (errno, errbuf, sizeof (errbuf)));
845 }
846 }
848 static _Bool plugin_is_loaded (char const *name)
849 {
850 int status;
852 if (plugins_loaded == NULL)
853 plugins_loaded = c_avl_create ((void *) strcasecmp);
854 assert (plugins_loaded != NULL);
856 status = c_avl_get (plugins_loaded, name, /* ret_value = */ NULL);
857 return (status == 0);
858 }
860 static int plugin_mark_loaded (char const *name)
861 {
862 char *name_copy;
863 int status;
865 name_copy = strdup (name);
866 if (name_copy == NULL)
867 return (ENOMEM);
869 status = c_avl_insert (plugins_loaded,
870 /* key = */ name_copy, /* value = */ NULL);
871 return (status);
872 }
874 static void plugin_free_loaded ()
875 {
876 void *key;
877 void *value;
879 if (plugins_loaded == NULL)
880 return;
882 while (c_avl_pick (plugins_loaded, &key, &value) == 0)
883 {
884 sfree (key);
885 assert (value == NULL);
886 }
888 c_avl_destroy (plugins_loaded);
889 plugins_loaded = NULL;
890 }
892 #define BUFSIZE 512
893 int plugin_load (char const *plugin_name, uint32_t flags)
894 {
895 DIR *dh;
896 const char *dir;
897 char filename[BUFSIZE] = "";
898 char typename[BUFSIZE];
899 int typename_len;
900 int ret;
901 struct stat statbuf;
902 struct dirent *de;
903 int status;
905 if (plugin_name == NULL)
906 return (EINVAL);
908 /* Check if plugin is already loaded and don't do anything in this
909 * case. */
910 if (plugin_is_loaded (plugin_name))
911 return (0);
913 dir = plugin_get_dir ();
914 ret = 1;
916 /*
917 * XXX: Magic at work:
918 *
919 * Some of the language bindings, for example the Python and Perl
920 * plugins, need to be able to export symbols to the scripts they run.
921 * For this to happen, the "Globals" flag needs to be set.
922 * Unfortunately, this technical detail is hard to explain to the
923 * average user and she shouldn't have to worry about this, ideally.
924 * So in order to save everyone's sanity use a different default for a
925 * handful of special plugins. --octo
926 */
927 if ((strcasecmp ("perl", plugin_name) == 0)
928 || (strcasecmp ("python", plugin_name) == 0))
929 flags |= PLUGIN_FLAGS_GLOBAL;
931 /* `cpu' should not match `cpufreq'. To solve this we add `.so' to the
932 * type when matching the filename */
933 status = ssnprintf (typename, sizeof (typename), "%s.so", plugin_name);
934 if ((status < 0) || ((size_t) status >= sizeof (typename)))
935 {
936 WARNING ("plugin_load: Filename too long: \"%s.so\"", plugin_name);
937 return (-1);
938 }
939 typename_len = strlen (typename);
941 if ((dh = opendir (dir)) == NULL)
942 {
943 char errbuf[1024];
944 ERROR ("plugin_load: opendir (%s) failed: %s", dir,
945 sstrerror (errno, errbuf, sizeof (errbuf)));
946 return (-1);
947 }
949 while ((de = readdir (dh)) != NULL)
950 {
951 if (strncasecmp (de->d_name, typename, typename_len))
952 continue;
954 status = ssnprintf (filename, sizeof (filename),
955 "%s/%s", dir, de->d_name);
956 if ((status < 0) || ((size_t) status >= sizeof (filename)))
957 {
958 WARNING ("plugin_load: Filename too long: \"%s/%s\"",
959 dir, de->d_name);
960 continue;
961 }
963 if (lstat (filename, &statbuf) == -1)
964 {
965 char errbuf[1024];
966 WARNING ("plugin_load: stat (\"%s\") failed: %s",
967 filename,
968 sstrerror (errno, errbuf, sizeof (errbuf)));
969 continue;
970 }
971 else if (!S_ISREG (statbuf.st_mode))
972 {
973 /* don't follow symlinks */
974 WARNING ("plugin_load: %s is not a regular file.",
975 filename);
976 continue;
977 }
979 status = plugin_load_file (filename, flags);
980 if (status == 0)
981 {
982 /* success */
983 plugin_mark_loaded (plugin_name);
984 ret = 0;
985 break;
986 }
987 else
988 {
989 ERROR ("plugin_load: Load plugin \"%s\" failed with "
990 "status %i.", plugin_name, status);
991 }
992 }
994 closedir (dh);
996 if (filename[0] == 0)
997 ERROR ("plugin_load: Could not find plugin \"%s\" in %s",
998 plugin_name, dir);
1000 return (ret);
1001 }
1003 /*
1004 * The `register_*' functions follow
1005 */
1006 int plugin_register_config (const char *name,
1007 int (*callback) (const char *key, const char *val),
1008 const char **keys, int keys_num)
1009 {
1010 cf_register (name, callback, keys, keys_num);
1011 return (0);
1012 } /* int plugin_register_config */
1014 int plugin_register_complex_config (const char *type,
1015 int (*callback) (oconfig_item_t *))
1016 {
1017 return (cf_register_complex (type, callback));
1018 } /* int plugin_register_complex_config */
1020 int plugin_register_init (const char *name,
1021 int (*callback) (void))
1022 {
1023 return (create_register_callback (&list_init, name, (void *) callback,
1024 /* user_data = */ NULL));
1025 } /* plugin_register_init */
1027 static int plugin_compare_read_func (const void *arg0, const void *arg1)
1028 {
1029 const read_func_t *rf0;
1030 const read_func_t *rf1;
1032 rf0 = arg0;
1033 rf1 = arg1;
1035 if (rf0->rf_next_read < rf1->rf_next_read)
1036 return (-1);
1037 else if (rf0->rf_next_read > rf1->rf_next_read)
1038 return (1);
1039 else
1040 return (0);
1041 } /* int plugin_compare_read_func */
1043 /* Add a read function to both, the heap and a linked list. The linked list if
1044 * used to look-up read functions, especially for the remove function. The heap
1045 * is used to determine which plugin to read next. */
1046 static int plugin_insert_read (read_func_t *rf)
1047 {
1048 int status;
1049 llentry_t *le;
1051 rf->rf_next_read = cdtime ();
1052 rf->rf_effective_interval = rf->rf_interval;
1054 pthread_mutex_lock (&read_lock);
1056 if (read_list == NULL)
1057 {
1058 read_list = llist_create ();
1059 if (read_list == NULL)
1060 {
1061 pthread_mutex_unlock (&read_lock);
1062 ERROR ("plugin_insert_read: read_list failed.");
1063 return (-1);
1064 }
1065 }
1067 if (read_heap == NULL)
1068 {
1069 read_heap = c_heap_create (plugin_compare_read_func);
1070 if (read_heap == NULL)
1071 {
1072 pthread_mutex_unlock (&read_lock);
1073 ERROR ("plugin_insert_read: c_heap_create failed.");
1074 return (-1);
1075 }
1076 }
1078 le = llist_search (read_list, rf->rf_name);
1079 if (le != NULL)
1080 {
1081 pthread_mutex_unlock (&read_lock);
1082 WARNING ("The read function \"%s\" is already registered. "
1083 "Check for duplicate \"LoadPlugin\" lines "
1084 "in your configuration!",
1085 rf->rf_name);
1086 return (EINVAL);
1087 }
1089 le = llentry_create (rf->rf_name, rf);
1090 if (le == NULL)
1091 {
1092 pthread_mutex_unlock (&read_lock);
1093 ERROR ("plugin_insert_read: llentry_create failed.");
1094 return (-1);
1095 }
1097 status = c_heap_insert (read_heap, rf);
1098 if (status != 0)
1099 {
1100 pthread_mutex_unlock (&read_lock);
1101 ERROR ("plugin_insert_read: c_heap_insert failed.");
1102 llentry_destroy (le);
1103 return (-1);
1104 }
1106 /* This does not fail. */
1107 llist_append (read_list, le);
1109 /* Wake up all the read threads. */
1110 pthread_cond_broadcast (&read_cond);
1111 pthread_mutex_unlock (&read_lock);
1112 return (0);
1113 } /* int plugin_insert_read */
1115 int plugin_register_read (const char *name,
1116 int (*callback) (void))
1117 {
1118 read_func_t *rf;
1119 int status;
1121 rf = malloc (sizeof (*rf));
1122 if (rf == NULL)
1123 {
1124 ERROR ("plugin_register_read: malloc failed.");
1125 return (ENOMEM);
1126 }
1128 memset (rf, 0, sizeof (read_func_t));
1129 rf->rf_callback = (void *) callback;
1130 rf->rf_udata.data = NULL;
1131 rf->rf_udata.free_func = NULL;
1132 rf->rf_ctx = plugin_get_ctx ();
1133 rf->rf_group[0] = '\0';
1134 rf->rf_name = strdup (name);
1135 rf->rf_type = RF_SIMPLE;
1136 rf->rf_interval = plugin_get_interval ();
1138 status = plugin_insert_read (rf);
1139 if (status != 0)
1140 sfree (rf);
1142 return (status);
1143 } /* int plugin_register_read */
1145 int plugin_register_complex_read (const char *group, const char *name,
1146 plugin_read_cb callback,
1147 const struct timespec *interval,
1148 user_data_t *user_data)
1149 {
1150 read_func_t *rf;
1151 int status;
1153 rf = malloc (sizeof (*rf));
1154 if (rf == NULL)
1155 {
1156 ERROR ("plugin_register_complex_read: malloc failed.");
1157 return (ENOMEM);
1158 }
1160 memset (rf, 0, sizeof (read_func_t));
1161 rf->rf_callback = (void *) callback;
1162 if (group != NULL)
1163 sstrncpy (rf->rf_group, group, sizeof (rf->rf_group));
1164 else
1165 rf->rf_group[0] = '\0';
1166 rf->rf_name = strdup (name);
1167 rf->rf_type = RF_COMPLEX;
1168 if (interval != NULL)
1169 rf->rf_interval = TIMESPEC_TO_CDTIME_T (interval);
1170 else
1171 rf->rf_interval = plugin_get_interval ();
1173 /* Set user data */
1174 if (user_data == NULL)
1175 {
1176 rf->rf_udata.data = NULL;
1177 rf->rf_udata.free_func = NULL;
1178 }
1179 else
1180 {
1181 rf->rf_udata = *user_data;
1182 }
1184 rf->rf_ctx = plugin_get_ctx ();
1186 status = plugin_insert_read (rf);
1187 if (status != 0)
1188 sfree (rf);
1190 return (status);
1191 } /* int plugin_register_complex_read */
1193 int plugin_register_write (const char *name,
1194 plugin_write_cb callback, user_data_t *ud)
1195 {
1196 return (create_register_callback (&list_write, name,
1197 (void *) callback, ud));
1198 } /* int plugin_register_write */
1200 int plugin_register_flush (const char *name,
1201 plugin_flush_cb callback, user_data_t *ud)
1202 {
1203 return (create_register_callback (&list_flush, name,
1204 (void *) callback, ud));
1205 } /* int plugin_register_flush */
1207 int plugin_register_missing (const char *name,
1208 plugin_missing_cb callback, user_data_t *ud)
1209 {
1210 return (create_register_callback (&list_missing, name,
1211 (void *) callback, ud));
1212 } /* int plugin_register_missing */
1214 int plugin_register_shutdown (const char *name,
1215 int (*callback) (void))
1216 {
1217 return (create_register_callback (&list_shutdown, name,
1218 (void *) callback, /* user_data = */ NULL));
1219 } /* int plugin_register_shutdown */
1221 int plugin_register_data_set (const data_set_t *ds)
1222 {
1223 data_set_t *ds_copy;
1224 int i;
1226 if ((data_sets != NULL)
1227 && (c_avl_get (data_sets, ds->type, NULL) == 0))
1228 {
1229 NOTICE ("Replacing DS `%s' with another version.", ds->type);
1230 plugin_unregister_data_set (ds->type);
1231 }
1232 else if (data_sets == NULL)
1233 {
1234 data_sets = c_avl_create ((int (*) (const void *, const void *)) strcmp);
1235 if (data_sets == NULL)
1236 return (-1);
1237 }
1239 ds_copy = (data_set_t *) malloc (sizeof (data_set_t));
1240 if (ds_copy == NULL)
1241 return (-1);
1242 memcpy(ds_copy, ds, sizeof (data_set_t));
1244 ds_copy->ds = (data_source_t *) malloc (sizeof (data_source_t)
1245 * ds->ds_num);
1246 if (ds_copy->ds == NULL)
1247 {
1248 free (ds_copy);
1249 return (-1);
1250 }
1252 for (i = 0; i < ds->ds_num; i++)
1253 memcpy (ds_copy->ds + i, ds->ds + i, sizeof (data_source_t));
1255 return (c_avl_insert (data_sets, (void *) ds_copy->type, (void *) ds_copy));
1256 } /* int plugin_register_data_set */
1258 int plugin_register_log (const char *name,
1259 plugin_log_cb callback, user_data_t *ud)
1260 {
1261 return (create_register_callback (&list_log, name,
1262 (void *) callback, ud));
1263 } /* int plugin_register_log */
1265 int plugin_register_notification (const char *name,
1266 plugin_notification_cb callback, user_data_t *ud)
1267 {
1268 return (create_register_callback (&list_notification, name,
1269 (void *) callback, ud));
1270 } /* int plugin_register_log */
1272 int plugin_unregister_config (const char *name)
1273 {
1274 cf_unregister (name);
1275 return (0);
1276 } /* int plugin_unregister_config */
1278 int plugin_unregister_complex_config (const char *name)
1279 {
1280 cf_unregister_complex (name);
1281 return (0);
1282 } /* int plugin_unregister_complex_config */
1284 int plugin_unregister_init (const char *name)
1285 {
1286 return (plugin_unregister (list_init, name));
1287 }
1289 int plugin_unregister_read (const char *name) /* {{{ */
1290 {
1291 llentry_t *le;
1292 read_func_t *rf;
1294 if (name == NULL)
1295 return (-ENOENT);
1297 pthread_mutex_lock (&read_lock);
1299 if (read_list == NULL)
1300 {
1301 pthread_mutex_unlock (&read_lock);
1302 return (-ENOENT);
1303 }
1305 le = llist_search (read_list, name);
1306 if (le == NULL)
1307 {
1308 pthread_mutex_unlock (&read_lock);
1309 WARNING ("plugin_unregister_read: No such read function: %s",
1310 name);
1311 return (-ENOENT);
1312 }
1314 llist_remove (read_list, le);
1316 rf = le->value;
1317 assert (rf != NULL);
1318 rf->rf_type = RF_REMOVE;
1320 pthread_mutex_unlock (&read_lock);
1322 llentry_destroy (le);
1324 DEBUG ("plugin_unregister_read: Marked `%s' for removal.", name);
1326 return (0);
1327 } /* }}} int plugin_unregister_read */
1329 static int compare_read_func_group (llentry_t *e, void *ud) /* {{{ */
1330 {
1331 read_func_t *rf = e->value;
1332 char *group = ud;
1334 return strcmp (rf->rf_group, (const char *)group);
1335 } /* }}} int compare_read_func_group */
1337 int plugin_unregister_read_group (const char *group) /* {{{ */
1338 {
1339 llentry_t *le;
1340 read_func_t *rf;
1342 int found = 0;
1344 if (group == NULL)
1345 return (-ENOENT);
1347 pthread_mutex_lock (&read_lock);
1349 if (read_list == NULL)
1350 {
1351 pthread_mutex_unlock (&read_lock);
1352 return (-ENOENT);
1353 }
1355 while (42)
1356 {
1357 le = llist_search_custom (read_list,
1358 compare_read_func_group, (void *)group);
1360 if (le == NULL)
1361 break;
1363 ++found;
1365 llist_remove (read_list, le);
1367 rf = le->value;
1368 assert (rf != NULL);
1369 rf->rf_type = RF_REMOVE;
1371 llentry_destroy (le);
1373 DEBUG ("plugin_unregister_read_group: "
1374 "Marked `%s' (group `%s') for removal.",
1375 rf->rf_name, group);
1376 }
1378 pthread_mutex_unlock (&read_lock);
1380 if (found == 0)
1381 {
1382 WARNING ("plugin_unregister_read_group: No such "
1383 "group of read function: %s", group);
1384 return (-ENOENT);
1385 }
1387 return (0);
1388 } /* }}} int plugin_unregister_read_group */
1390 int plugin_unregister_write (const char *name)
1391 {
1392 return (plugin_unregister (list_write, name));
1393 }
1395 int plugin_unregister_flush (const char *name)
1396 {
1397 return (plugin_unregister (list_flush, name));
1398 }
1400 int plugin_unregister_missing (const char *name)
1401 {
1402 return (plugin_unregister (list_missing, name));
1403 }
1405 int plugin_unregister_shutdown (const char *name)
1406 {
1407 return (plugin_unregister (list_shutdown, name));
1408 }
1410 int plugin_unregister_data_set (const char *name)
1411 {
1412 data_set_t *ds;
1414 if (data_sets == NULL)
1415 return (-1);
1417 if (c_avl_remove (data_sets, name, NULL, (void *) &ds) != 0)
1418 return (-1);
1420 sfree (ds->ds);
1421 sfree (ds);
1423 return (0);
1424 } /* int plugin_unregister_data_set */
1426 int plugin_unregister_log (const char *name)
1427 {
1428 return (plugin_unregister (list_log, name));
1429 }
1431 int plugin_unregister_notification (const char *name)
1432 {
1433 return (plugin_unregister (list_notification, name));
1434 }
1436 void plugin_init_all (void)
1437 {
1438 char const *chain_name;
1439 long write_threads_num;
1440 llentry_t *le;
1441 int status;
1443 /* Init the value cache */
1444 uc_init ();
1446 chain_name = global_option_get ("PreCacheChain");
1447 pre_cache_chain = fc_chain_get_by_name (chain_name);
1449 chain_name = global_option_get ("PostCacheChain");
1450 post_cache_chain = fc_chain_get_by_name (chain_name);
1452 write_limit_high = global_option_get_long ("WriteQueueLimitHigh",
1453 /* default = */ 0);
1454 if (write_limit_high < 0)
1455 {
1456 ERROR ("WriteQueueLimitHigh must be positive or zero.");
1457 write_limit_high = 0;
1458 }
1460 write_limit_low = global_option_get_long ("WriteQueueLimitLow",
1461 /* default = */ write_limit_high / 2);
1462 if (write_limit_low < 0)
1463 {
1464 ERROR ("WriteQueueLimitLow must be positive or zero.");
1465 write_limit_low = write_limit_high / 2;
1466 }
1467 else if (write_limit_low > write_limit_high)
1468 {
1469 ERROR ("WriteQueueLimitLow must not be larger than "
1470 "WriteQueueLimitHigh.");
1471 write_limit_low = write_limit_high;
1472 }
1474 write_threads_num = global_option_get_long ("WriteThreads",
1475 /* default = */ 5);
1476 if (write_threads_num < 1)
1477 {
1478 ERROR ("WriteThreads must be positive.");
1479 write_threads_num = 5;
1480 }
1482 start_write_threads ((size_t) write_threads_num);
1484 if ((list_init == NULL) && (read_heap == NULL))
1485 return;
1487 /* Calling all init callbacks before checking if read callbacks
1488 * are available allows the init callbacks to register the read
1489 * callback. */
1490 le = llist_head (list_init);
1491 while (le != NULL)
1492 {
1493 callback_func_t *cf;
1494 plugin_init_cb callback;
1495 plugin_ctx_t old_ctx;
1497 cf = le->value;
1498 old_ctx = plugin_set_ctx (cf->cf_ctx);
1499 callback = cf->cf_callback;
1500 status = (*callback) ();
1501 plugin_set_ctx (old_ctx);
1503 if (status != 0)
1504 {
1505 ERROR ("Initialization of plugin `%s' "
1506 "failed with status %i. "
1507 "Plugin will be unloaded.",
1508 le->key, status);
1509 /* Plugins that register read callbacks from the init
1510 * callback should take care of appropriate error
1511 * handling themselves. */
1512 /* FIXME: Unload _all_ functions */
1513 plugin_unregister_read (le->key);
1514 }
1516 le = le->next;
1517 }
1519 /* Start read-threads */
1520 if (read_heap != NULL)
1521 {
1522 const char *rt;
1523 int num;
1524 rt = global_option_get ("ReadThreads");
1525 num = atoi (rt);
1526 if (num != -1)
1527 start_read_threads ((num > 0) ? num : 5);
1528 }
1529 } /* void plugin_init_all */
1531 /* TODO: Rename this function. */
1532 void plugin_read_all (void)
1533 {
1534 uc_check_timeout ();
1536 return;
1537 } /* void plugin_read_all */
1539 /* Read function called when the `-T' command line argument is given. */
1540 int plugin_read_all_once (void)
1541 {
1542 int status;
1543 int return_status = 0;
1545 if (read_heap == NULL)
1546 {
1547 NOTICE ("No read-functions are registered.");
1548 return (0);
1549 }
1551 while (42)
1552 {
1553 read_func_t *rf;
1554 plugin_ctx_t old_ctx;
1556 rf = c_heap_get_root (read_heap);
1557 if (rf == NULL)
1558 break;
1560 old_ctx = plugin_set_ctx (rf->rf_ctx);
1562 if (rf->rf_type == RF_SIMPLE)
1563 {
1564 int (*callback) (void);
1566 callback = rf->rf_callback;
1567 status = (*callback) ();
1568 }
1569 else
1570 {
1571 plugin_read_cb callback;
1573 callback = rf->rf_callback;
1574 status = (*callback) (&rf->rf_udata);
1575 }
1577 plugin_set_ctx (old_ctx);
1579 if (status != 0)
1580 {
1581 NOTICE ("read-function of plugin `%s' failed.",
1582 rf->rf_name);
1583 return_status = -1;
1584 }
1586 destroy_callback ((void *) rf);
1587 }
1589 return (return_status);
1590 } /* int plugin_read_all_once */
1592 int plugin_write (const char *plugin, /* {{{ */
1593 const data_set_t *ds, const value_list_t *vl)
1594 {
1595 llentry_t *le;
1596 int status;
1598 if (vl == NULL)
1599 return (EINVAL);
1601 if (list_write == NULL)
1602 return (ENOENT);
1604 if (ds == NULL)
1605 {
1606 ds = plugin_get_ds (vl->type);
1607 if (ds == NULL)
1608 {
1609 ERROR ("plugin_write: Unable to lookup type `%s'.", vl->type);
1610 return (ENOENT);
1611 }
1612 }
1614 if (plugin == NULL)
1615 {
1616 int success = 0;
1617 int failure = 0;
1619 le = llist_head (list_write);
1620 while (le != NULL)
1621 {
1622 callback_func_t *cf = le->value;
1623 plugin_write_cb callback;
1625 /* do not switch plugin context; rather keep the context (interval)
1626 * information of the calling read plugin */
1628 DEBUG ("plugin: plugin_write: Writing values via %s.", le->key);
1629 callback = cf->cf_callback;
1630 status = (*callback) (ds, vl, &cf->cf_udata);
1631 if (status != 0)
1632 failure++;
1633 else
1634 success++;
1636 le = le->next;
1637 }
1639 if ((success == 0) && (failure != 0))
1640 status = -1;
1641 else
1642 status = 0;
1643 }
1644 else /* plugin != NULL */
1645 {
1646 callback_func_t *cf;
1647 plugin_write_cb callback;
1649 le = llist_head (list_write);
1650 while (le != NULL)
1651 {
1652 if (strcasecmp (plugin, le->key) == 0)
1653 break;
1655 le = le->next;
1656 }
1658 if (le == NULL)
1659 return (ENOENT);
1661 cf = le->value;
1663 /* do not switch plugin context; rather keep the context (interval)
1664 * information of the calling read plugin */
1666 DEBUG ("plugin: plugin_write: Writing values via %s.", le->key);
1667 callback = cf->cf_callback;
1668 status = (*callback) (ds, vl, &cf->cf_udata);
1669 }
1671 return (status);
1672 } /* }}} int plugin_write */
1674 int plugin_flush (const char *plugin, cdtime_t timeout, const char *identifier)
1675 {
1676 llentry_t *le;
1678 if (list_flush == NULL)
1679 return (0);
1681 le = llist_head (list_flush);
1682 while (le != NULL)
1683 {
1684 callback_func_t *cf;
1685 plugin_flush_cb callback;
1686 plugin_ctx_t old_ctx;
1688 if ((plugin != NULL)
1689 && (strcmp (plugin, le->key) != 0))
1690 {
1691 le = le->next;
1692 continue;
1693 }
1695 cf = le->value;
1696 old_ctx = plugin_set_ctx (cf->cf_ctx);
1697 callback = cf->cf_callback;
1699 (*callback) (timeout, identifier, &cf->cf_udata);
1701 plugin_set_ctx (old_ctx);
1703 le = le->next;
1704 }
1705 return (0);
1706 } /* int plugin_flush */
1708 void plugin_shutdown_all (void)
1709 {
1710 llentry_t *le;
1712 stop_read_threads ();
1714 destroy_all_callbacks (&list_init);
1716 pthread_mutex_lock (&read_lock);
1717 llist_destroy (read_list);
1718 read_list = NULL;
1719 pthread_mutex_unlock (&read_lock);
1721 destroy_read_heap ();
1723 plugin_flush (/* plugin = */ NULL,
1724 /* timeout = */ 0,
1725 /* identifier = */ NULL);
1727 le = NULL;
1728 if (list_shutdown != NULL)
1729 le = llist_head (list_shutdown);
1731 while (le != NULL)
1732 {
1733 callback_func_t *cf;
1734 plugin_shutdown_cb callback;
1735 plugin_ctx_t old_ctx;
1737 cf = le->value;
1738 old_ctx = plugin_set_ctx (cf->cf_ctx);
1739 callback = cf->cf_callback;
1741 /* Advance the pointer before calling the callback allows
1742 * shutdown functions to unregister themselves. If done the
1743 * other way around the memory `le' points to will be freed
1744 * after callback returns. */
1745 le = le->next;
1747 (*callback) ();
1749 plugin_set_ctx (old_ctx);
1750 }
1752 stop_write_threads ();
1754 /* Write plugins which use the `user_data' pointer usually need the
1755 * same data available to the flush callback. If this is the case, set
1756 * the free_function to NULL when registering the flush callback and to
1757 * the real free function when registering the write callback. This way
1758 * the data isn't freed twice. */
1759 destroy_all_callbacks (&list_flush);
1760 destroy_all_callbacks (&list_missing);
1761 destroy_all_callbacks (&list_write);
1763 destroy_all_callbacks (&list_notification);
1764 destroy_all_callbacks (&list_shutdown);
1765 destroy_all_callbacks (&list_log);
1767 plugin_free_loaded ();
1768 } /* void plugin_shutdown_all */
1770 int plugin_dispatch_missing (const value_list_t *vl) /* {{{ */
1771 {
1772 llentry_t *le;
1774 if (list_missing == NULL)
1775 return (0);
1777 le = llist_head (list_missing);
1778 while (le != NULL)
1779 {
1780 callback_func_t *cf;
1781 plugin_missing_cb callback;
1782 plugin_ctx_t old_ctx;
1783 int status;
1785 cf = le->value;
1786 old_ctx = plugin_set_ctx (cf->cf_ctx);
1787 callback = cf->cf_callback;
1789 status = (*callback) (vl, &cf->cf_udata);
1790 plugin_set_ctx (old_ctx);
1791 if (status != 0)
1792 {
1793 if (status < 0)
1794 {
1795 ERROR ("plugin_dispatch_missing: Callback function \"%s\" "
1796 "failed with status %i.",
1797 le->key, status);
1798 return (status);
1799 }
1800 else
1801 {
1802 return (0);
1803 }
1804 }
1806 le = le->next;
1807 }
1808 return (0);
1809 } /* int }}} plugin_dispatch_missing */
1811 static int plugin_dispatch_values_internal (value_list_t *vl)
1812 {
1813 int status;
1814 static c_complain_t no_write_complaint = C_COMPLAIN_INIT_STATIC;
1816 value_t *saved_values;
1817 int saved_values_len;
1819 data_set_t *ds;
1821 int free_meta_data = 0;
1823 if ((vl == NULL) || (vl->type[0] == 0)
1824 || (vl->values == NULL) || (vl->values_len < 1))
1825 {
1826 ERROR ("plugin_dispatch_values: Invalid value list "
1827 "from plugin %s.", vl->plugin);
1828 return (-1);
1829 }
1831 /* Free meta data only if the calling function didn't specify any. In
1832 * this case matches and targets may add some and the calling function
1833 * may not expect (and therefore free) that data. */
1834 if (vl->meta == NULL)
1835 free_meta_data = 1;
1837 if (list_write == NULL)
1838 c_complain_once (LOG_WARNING, &no_write_complaint,
1839 "plugin_dispatch_values: No write callback has been "
1840 "registered. Please load at least one output plugin, "
1841 "if you want the collected data to be stored.");
1843 if (data_sets == NULL)
1844 {
1845 ERROR ("plugin_dispatch_values: No data sets registered. "
1846 "Could the types database be read? Check "
1847 "your `TypesDB' setting!");
1848 return (-1);
1849 }
1851 if (c_avl_get (data_sets, vl->type, (void *) &ds) != 0)
1852 {
1853 char ident[6 * DATA_MAX_NAME_LEN];
1855 FORMAT_VL (ident, sizeof (ident), vl);
1856 INFO ("plugin_dispatch_values: Dataset not found: %s "
1857 "(from \"%s\"), check your types.db!",
1858 vl->type, ident);
1859 return (-1);
1860 }
1862 /* Assured by plugin_value_list_clone(). The time is determined at
1863 * _enqueue_ time. */
1864 assert (vl->time != 0);
1865 assert (vl->interval != 0);
1867 DEBUG ("plugin_dispatch_values: time = %.3f; interval = %.3f; "
1868 "host = %s; "
1869 "plugin = %s; plugin_instance = %s; "
1870 "type = %s; type_instance = %s;",
1871 CDTIME_T_TO_DOUBLE (vl->time),
1872 CDTIME_T_TO_DOUBLE (vl->interval),
1873 vl->host,
1874 vl->plugin, vl->plugin_instance,
1875 vl->type, vl->type_instance);
1877 #if COLLECT_DEBUG
1878 assert (0 == strcmp (ds->type, vl->type));
1879 #else
1880 if (0 != strcmp (ds->type, vl->type))
1881 WARNING ("plugin_dispatch_values: (ds->type = %s) != (vl->type = %s)",
1882 ds->type, vl->type);
1883 #endif
1885 #if COLLECT_DEBUG
1886 assert (ds->ds_num == vl->values_len);
1887 #else
1888 if (ds->ds_num != vl->values_len)
1889 {
1890 ERROR ("plugin_dispatch_values: ds->type = %s: "
1891 "(ds->ds_num = %i) != "
1892 "(vl->values_len = %i)",
1893 ds->type, ds->ds_num, vl->values_len);
1894 return (-1);
1895 }
1896 #endif
1898 escape_slashes (vl->host, sizeof (vl->host));
1899 escape_slashes (vl->plugin, sizeof (vl->plugin));
1900 escape_slashes (vl->plugin_instance, sizeof (vl->plugin_instance));
1901 escape_slashes (vl->type, sizeof (vl->type));
1902 escape_slashes (vl->type_instance, sizeof (vl->type_instance));
1904 /* Copy the values. This way, we can assure `targets' that they get
1905 * dynamically allocated values, which they can free and replace if
1906 * they like. */
1907 if ((pre_cache_chain != NULL) || (post_cache_chain != NULL))
1908 {
1909 saved_values = vl->values;
1910 saved_values_len = vl->values_len;
1912 vl->values = (value_t *) calloc (vl->values_len,
1913 sizeof (*vl->values));
1914 if (vl->values == NULL)
1915 {
1916 ERROR ("plugin_dispatch_values: calloc failed.");
1917 vl->values = saved_values;
1918 return (-1);
1919 }
1920 memcpy (vl->values, saved_values,
1921 vl->values_len * sizeof (*vl->values));
1922 }
1923 else /* if ((pre == NULL) && (post == NULL)) */
1924 {
1925 saved_values = NULL;
1926 saved_values_len = 0;
1927 }
1929 if (pre_cache_chain != NULL)
1930 {
1931 status = fc_process_chain (ds, vl, pre_cache_chain);
1932 if (status < 0)
1933 {
1934 WARNING ("plugin_dispatch_values: Running the "
1935 "pre-cache chain failed with "
1936 "status %i (%#x).",
1937 status, status);
1938 }
1939 else if (status == FC_TARGET_STOP)
1940 {
1941 /* Restore the state of the value_list so that plugins
1942 * don't get confused.. */
1943 if (saved_values != NULL)
1944 {
1945 free (vl->values);
1946 vl->values = saved_values;
1947 vl->values_len = saved_values_len;
1948 }
1949 return (0);
1950 }
1951 }
1953 /* Update the value cache */
1954 uc_update (ds, vl);
1956 if (post_cache_chain != NULL)
1957 {
1958 status = fc_process_chain (ds, vl, post_cache_chain);
1959 if (status < 0)
1960 {
1961 WARNING ("plugin_dispatch_values: Running the "
1962 "post-cache chain failed with "
1963 "status %i (%#x).",
1964 status, status);
1965 }
1966 }
1967 else
1968 fc_default_action (ds, vl);
1970 /* Restore the state of the value_list so that plugins don't get
1971 * confused.. */
1972 if (saved_values != NULL)
1973 {
1974 free (vl->values);
1975 vl->values = saved_values;
1976 vl->values_len = saved_values_len;
1977 }
1979 if ((free_meta_data != 0) && (vl->meta != NULL))
1980 {
1981 meta_data_destroy (vl->meta);
1982 vl->meta = NULL;
1983 }
1985 return (0);
1986 } /* int plugin_dispatch_values_internal */
1988 static _Bool drop_metric(void) {
1989 _Bool drop = 0;
1990 int wq_len = write_queue_length;
1991 /* We store write_queue_length in a local variable because other threads may update write_queue_length.
1992 * Having this in a local variable (like a cache) is better : we do not need a lock */
1994 if(wq_len < write_limit_low) return(0);
1996 if((write_limit_high > 0) && (wq_len > write_limit_low)) {
1997 if(wq_len >= write_limit_high) {
1998 /* if high == low, we come here too */
1999 drop = 1;
2000 } else {
2001 /* here, high != low */
2002 long probability_to_drop;
2003 long n;
2005 probability_to_drop = (wq_len - write_limit_low);
2007 n = cdrand_range(write_limit_low, write_limit_high);
2009 /* Let's have X = high - low.
2010 * n is in range [0..X]
2011 * probability_to_drop is in range [1..X[
2012 * probability_to_drop gets bigger when wq_len gets bigger.
2013 */
2014 if(n <= probability_to_drop) {
2015 drop = 1;
2016 }
2017 }
2018 }
2019 if(drop) {
2020 cdtime_t now = cdtime();
2021 if((now - last_drop_time) > TIME_T_TO_CDTIME_T (60)) {
2022 last_drop_time = now;
2023 /* If you want to count dropped metrics, don't forget to add a lock here */
2024 /* dropped_metrics++; */
2025 ERROR ("plugin_dispatch_values : Low water mark reached, dropping a metric");
2026 }
2027 }
2028 return(drop);
2029 }
2031 int plugin_dispatch_values (value_list_t const *vl)
2032 {
2033 int status;
2035 if(drop_metric ()) return(0);
2037 status = plugin_write_enqueue (vl);
2038 if (status != 0)
2039 {
2040 char errbuf[1024];
2041 ERROR ("plugin_dispatch_values: plugin_write_enqueue failed "
2042 "with status %i (%s).", status,
2043 sstrerror (status, errbuf, sizeof (errbuf)));
2044 return (status);
2045 }
2047 return (0);
2048 }
2050 int plugin_dispatch_notification (const notification_t *notif)
2051 {
2052 llentry_t *le;
2053 /* Possible TODO: Add flap detection here */
2055 DEBUG ("plugin_dispatch_notification: severity = %i; message = %s; "
2056 "time = %.3f; host = %s;",
2057 notif->severity, notif->message,
2058 CDTIME_T_TO_DOUBLE (notif->time), notif->host);
2060 /* Nobody cares for notifications */
2061 if (list_notification == NULL)
2062 return (-1);
2064 le = llist_head (list_notification);
2065 while (le != NULL)
2066 {
2067 callback_func_t *cf;
2068 plugin_notification_cb callback;
2069 int status;
2071 /* do not switch plugin context; rather keep the context
2072 * (interval) information of the calling plugin */
2074 cf = le->value;
2075 callback = cf->cf_callback;
2076 status = (*callback) (notif, &cf->cf_udata);
2077 if (status != 0)
2078 {
2079 WARNING ("plugin_dispatch_notification: Notification "
2080 "callback %s returned %i.",
2081 le->key, status);
2082 }
2084 le = le->next;
2085 }
2087 return (0);
2088 } /* int plugin_dispatch_notification */
2090 void plugin_log (int level, const char *format, ...)
2091 {
2092 char msg[1024];
2093 va_list ap;
2094 llentry_t *le;
2096 #if !COLLECT_DEBUG
2097 if (level >= LOG_DEBUG)
2098 return;
2099 #endif
2101 va_start (ap, format);
2102 vsnprintf (msg, sizeof (msg), format, ap);
2103 msg[sizeof (msg) - 1] = '\0';
2104 va_end (ap);
2106 if (list_log == NULL)
2107 {
2108 fprintf (stderr, "%s\n", msg);
2109 return;
2110 }
2112 le = llist_head (list_log);
2113 while (le != NULL)
2114 {
2115 callback_func_t *cf;
2116 plugin_log_cb callback;
2118 cf = le->value;
2119 callback = cf->cf_callback;
2121 /* do not switch plugin context; rather keep the context
2122 * (interval) information of the calling plugin */
2124 (*callback) (level, msg, &cf->cf_udata);
2126 le = le->next;
2127 }
2128 } /* void plugin_log */
2130 int parse_log_severity (const char *severity)
2131 {
2132 int log_level = -1;
2134 if ((0 == strcasecmp (severity, "emerg"))
2135 || (0 == strcasecmp (severity, "alert"))
2136 || (0 == strcasecmp (severity, "crit"))
2137 || (0 == strcasecmp (severity, "err")))
2138 log_level = LOG_ERR;
2139 else if (0 == strcasecmp (severity, "warning"))
2140 log_level = LOG_WARNING;
2141 else if (0 == strcasecmp (severity, "notice"))
2142 log_level = LOG_NOTICE;
2143 else if (0 == strcasecmp (severity, "info"))
2144 log_level = LOG_INFO;
2145 #if COLLECT_DEBUG
2146 else if (0 == strcasecmp (severity, "debug"))
2147 log_level = LOG_DEBUG;
2148 #endif /* COLLECT_DEBUG */
2150 return (log_level);
2151 } /* int parse_log_severity */
2153 int parse_notif_severity (const char *severity)
2154 {
2155 int notif_severity = -1;
2157 if (strcasecmp (severity, "FAILURE") == 0)
2158 notif_severity = NOTIF_FAILURE;
2159 else if (strcmp (severity, "OKAY") == 0)
2160 notif_severity = NOTIF_OKAY;
2161 else if ((strcmp (severity, "WARNING") == 0)
2162 || (strcmp (severity, "WARN") == 0))
2163 notif_severity = NOTIF_WARNING;
2165 return (notif_severity);
2166 } /* int parse_notif_severity */
2168 const data_set_t *plugin_get_ds (const char *name)
2169 {
2170 data_set_t *ds;
2172 if (data_sets == NULL)
2173 {
2174 ERROR ("plugin_get_ds: No data sets are defined yet.");
2175 return (NULL);
2176 }
2178 if (c_avl_get (data_sets, name, (void *) &ds) != 0)
2179 {
2180 DEBUG ("No such dataset registered: %s", name);
2181 return (NULL);
2182 }
2184 return (ds);
2185 } /* data_set_t *plugin_get_ds */
2187 static int plugin_notification_meta_add (notification_t *n,
2188 const char *name,
2189 enum notification_meta_type_e type,
2190 const void *value)
2191 {
2192 notification_meta_t *meta;
2193 notification_meta_t *tail;
2195 if ((n == NULL) || (name == NULL) || (value == NULL))
2196 {
2197 ERROR ("plugin_notification_meta_add: A pointer is NULL!");
2198 return (-1);
2199 }
2201 meta = (notification_meta_t *) malloc (sizeof (notification_meta_t));
2202 if (meta == NULL)
2203 {
2204 ERROR ("plugin_notification_meta_add: malloc failed.");
2205 return (-1);
2206 }
2207 memset (meta, 0, sizeof (notification_meta_t));
2209 sstrncpy (meta->name, name, sizeof (meta->name));
2210 meta->type = type;
2212 switch (type)
2213 {
2214 case NM_TYPE_STRING:
2215 {
2216 meta->nm_value.nm_string = strdup ((const char *) value);
2217 if (meta->nm_value.nm_string == NULL)
2218 {
2219 ERROR ("plugin_notification_meta_add: strdup failed.");
2220 sfree (meta);
2221 return (-1);
2222 }
2223 break;
2224 }
2225 case NM_TYPE_SIGNED_INT:
2226 {
2227 meta->nm_value.nm_signed_int = *((int64_t *) value);
2228 break;
2229 }
2230 case NM_TYPE_UNSIGNED_INT:
2231 {
2232 meta->nm_value.nm_unsigned_int = *((uint64_t *) value);
2233 break;
2234 }
2235 case NM_TYPE_DOUBLE:
2236 {
2237 meta->nm_value.nm_double = *((double *) value);
2238 break;
2239 }
2240 case NM_TYPE_BOOLEAN:
2241 {
2242 meta->nm_value.nm_boolean = *((_Bool *) value);
2243 break;
2244 }
2245 default:
2246 {
2247 ERROR ("plugin_notification_meta_add: Unknown type: %i", type);
2248 sfree (meta);
2249 return (-1);
2250 }
2251 } /* switch (type) */
2253 meta->next = NULL;
2254 tail = n->meta;
2255 while ((tail != NULL) && (tail->next != NULL))
2256 tail = tail->next;
2258 if (tail == NULL)
2259 n->meta = meta;
2260 else
2261 tail->next = meta;
2263 return (0);
2264 } /* int plugin_notification_meta_add */
2266 int plugin_notification_meta_add_string (notification_t *n,
2267 const char *name,
2268 const char *value)
2269 {
2270 return (plugin_notification_meta_add (n, name, NM_TYPE_STRING, value));
2271 }
2273 int plugin_notification_meta_add_signed_int (notification_t *n,
2274 const char *name,
2275 int64_t value)
2276 {
2277 return (plugin_notification_meta_add (n, name, NM_TYPE_SIGNED_INT, &value));
2278 }
2280 int plugin_notification_meta_add_unsigned_int (notification_t *n,
2281 const char *name,
2282 uint64_t value)
2283 {
2284 return (plugin_notification_meta_add (n, name, NM_TYPE_UNSIGNED_INT, &value));
2285 }
2287 int plugin_notification_meta_add_double (notification_t *n,
2288 const char *name,
2289 double value)
2290 {
2291 return (plugin_notification_meta_add (n, name, NM_TYPE_DOUBLE, &value));
2292 }
2294 int plugin_notification_meta_add_boolean (notification_t *n,
2295 const char *name,
2296 _Bool value)
2297 {
2298 return (plugin_notification_meta_add (n, name, NM_TYPE_BOOLEAN, &value));
2299 }
2301 int plugin_notification_meta_copy (notification_t *dst,
2302 const notification_t *src)
2303 {
2304 notification_meta_t *meta;
2306 assert (dst != NULL);
2307 assert (src != NULL);
2308 assert (dst != src);
2309 assert ((src->meta == NULL) || (src->meta != dst->meta));
2311 for (meta = src->meta; meta != NULL; meta = meta->next)
2312 {
2313 if (meta->type == NM_TYPE_STRING)
2314 plugin_notification_meta_add_string (dst, meta->name,
2315 meta->nm_value.nm_string);
2316 else if (meta->type == NM_TYPE_SIGNED_INT)
2317 plugin_notification_meta_add_signed_int (dst, meta->name,
2318 meta->nm_value.nm_signed_int);
2319 else if (meta->type == NM_TYPE_UNSIGNED_INT)
2320 plugin_notification_meta_add_unsigned_int (dst, meta->name,
2321 meta->nm_value.nm_unsigned_int);
2322 else if (meta->type == NM_TYPE_DOUBLE)
2323 plugin_notification_meta_add_double (dst, meta->name,
2324 meta->nm_value.nm_double);
2325 else if (meta->type == NM_TYPE_BOOLEAN)
2326 plugin_notification_meta_add_boolean (dst, meta->name,
2327 meta->nm_value.nm_boolean);
2328 }
2330 return (0);
2331 } /* int plugin_notification_meta_copy */
2333 int plugin_notification_meta_free (notification_meta_t *n)
2334 {
2335 notification_meta_t *this;
2336 notification_meta_t *next;
2338 if (n == NULL)
2339 {
2340 ERROR ("plugin_notification_meta_free: n == NULL!");
2341 return (-1);
2342 }
2344 this = n;
2345 while (this != NULL)
2346 {
2347 next = this->next;
2349 if (this->type == NM_TYPE_STRING)
2350 {
2351 free ((char *)this->nm_value.nm_string);
2352 this->nm_value.nm_string = NULL;
2353 }
2354 sfree (this);
2356 this = next;
2357 }
2359 return (0);
2360 } /* int plugin_notification_meta_free */
2362 static void plugin_ctx_destructor (void *ctx)
2363 {
2364 sfree (ctx);
2365 } /* void plugin_ctx_destructor */
2367 static plugin_ctx_t ctx_init = { /* interval = */ 0 };
2369 static plugin_ctx_t *plugin_ctx_create (void)
2370 {
2371 plugin_ctx_t *ctx;
2373 ctx = malloc (sizeof (*ctx));
2374 if (ctx == NULL) {
2375 char errbuf[1024];
2376 ERROR ("Failed to allocate plugin context: %s",
2377 sstrerror (errno, errbuf, sizeof (errbuf)));
2378 return NULL;
2379 }
2381 *ctx = ctx_init;
2382 assert (plugin_ctx_key_initialized);
2383 pthread_setspecific (plugin_ctx_key, ctx);
2384 DEBUG("Created new plugin context.");
2385 return (ctx);
2386 } /* int plugin_ctx_create */
2388 void plugin_init_ctx (void)
2389 {
2390 pthread_key_create (&plugin_ctx_key, plugin_ctx_destructor);
2391 plugin_ctx_key_initialized = 1;
2392 } /* void plugin_init_ctx */
2394 plugin_ctx_t plugin_get_ctx (void)
2395 {
2396 plugin_ctx_t *ctx;
2398 assert (plugin_ctx_key_initialized);
2399 ctx = pthread_getspecific (plugin_ctx_key);
2401 if (ctx == NULL) {
2402 ctx = plugin_ctx_create ();
2403 /* this must no happen -- exit() instead? */
2404 if (ctx == NULL)
2405 return ctx_init;
2406 }
2408 return (*ctx);
2409 } /* plugin_ctx_t plugin_get_ctx */
2411 plugin_ctx_t plugin_set_ctx (plugin_ctx_t ctx)
2412 {
2413 plugin_ctx_t *c;
2414 plugin_ctx_t old;
2416 assert (plugin_ctx_key_initialized);
2417 c = pthread_getspecific (plugin_ctx_key);
2419 if (c == NULL) {
2420 c = plugin_ctx_create ();
2421 /* this must no happen -- exit() instead? */
2422 if (c == NULL)
2423 return ctx_init;
2424 }
2426 old = *c;
2427 *c = ctx;
2429 return (old);
2430 } /* void plugin_set_ctx */
2432 cdtime_t plugin_get_interval (void)
2433 {
2434 cdtime_t interval;
2436 interval = plugin_get_ctx().interval;
2437 if (interval > 0)
2438 return interval;
2440 return cf_get_default_interval ();
2441 } /* cdtime_t plugin_get_interval */
2443 typedef struct {
2444 plugin_ctx_t ctx;
2445 void *(*start_routine) (void *);
2446 void *arg;
2447 } plugin_thread_t;
2449 static void *plugin_thread_start (void *arg)
2450 {
2451 plugin_thread_t *plugin_thread = arg;
2453 void *(*start_routine) (void *) = plugin_thread->start_routine;
2454 void *plugin_arg = plugin_thread->arg;
2456 plugin_set_ctx (plugin_thread->ctx);
2458 free (plugin_thread);
2460 return start_routine (plugin_arg);
2461 } /* void *plugin_thread_start */
2463 int plugin_thread_create (pthread_t *thread, const pthread_attr_t *attr,
2464 void *(*start_routine) (void *), void *arg)
2465 {
2466 plugin_thread_t *plugin_thread;
2468 plugin_thread = malloc (sizeof (*plugin_thread));
2469 if (plugin_thread == NULL)
2470 return -1;
2472 plugin_thread->ctx = plugin_get_ctx ();
2473 plugin_thread->start_routine = start_routine;
2474 plugin_thread->arg = arg;
2476 return pthread_create (thread, attr,
2477 plugin_thread_start, plugin_thread);
2478 } /* int plugin_thread_create */
2480 /* vim: set sw=8 ts=8 noet fdm=marker : */