2 * collectd - src/plugin.c
3 * Copyright (C) 2005-2008 Florian octo Forster
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.
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.
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
19 * Florian octo Forster <octo at verplant.org>
20 * Sebastian Harl <sh at tokkee.org>
33 #include "configfile.h"
34 #include "utils_avltree.h"
35 #include "utils_llist.h"
36 #include "utils_cache.h"
37 #include "utils_threshold.h"
46 int (*callback) (void);
47 enum { DONE = 0, TODO = 1, ACTIVE = 2 } needs_read;
49 typedef struct read_func_s read_func_t;
54 static llist_t *list_init;
55 static llist_t *list_read;
56 static llist_t *list_write;
57 static llist_t *list_flush;
58 static llist_t *list_shutdown;
59 static llist_t *list_log;
60 static llist_t *list_notification;
62 static c_avl_tree_t *data_sets;
64 static char *plugindir = NULL;
66 static int read_loop = 1;
67 static pthread_mutex_t read_lock = PTHREAD_MUTEX_INITIALIZER;
68 static pthread_cond_t read_cond = PTHREAD_COND_INITIALIZER;
69 static pthread_t *read_threads = NULL;
70 static int read_threads_num = 0;
75 static const char *plugin_get_dir (void)
77 if (plugindir == NULL)
83 static int register_callback (llist_t **list, const char *name, void *callback)
89 && ((*list = llist_create ()) == NULL))
92 le = llist_search (*list, name);
99 le = llentry_create (key, callback);
106 llist_append (*list, le);
110 le->value = callback;
114 } /* int register_callback */
116 static int plugin_unregister (llist_t *list, const char *name)
120 e = llist_search (list, name);
125 llist_remove (list, e);
130 } /* int plugin_unregister */
133 * (Try to) load the shared object `file'. Won't complain if it isn't a shared
134 * object, but it will bitch about a shared object not having a
135 * ``module_register'' symbol..
137 static int plugin_load_file (char *file)
140 void (*reg_handle) (void);
142 DEBUG ("file = %s", file);
145 lt_dlerror (); /* clear errors */
147 if ((dlh = lt_dlopen (file)) == NULL)
149 const char *error = lt_dlerror ();
151 ERROR ("lt_dlopen failed: %s", error);
152 fprintf (stderr, "lt_dlopen failed: %s\n", error);
156 if ((reg_handle = (void (*) (void)) lt_dlsym (dlh, "module_register")) == NULL)
158 WARNING ("Couldn't find symbol ``module_register'' in ``%s'': %s\n",
159 file, lt_dlerror ());
169 static void *plugin_read_thread (void *args)
176 pthread_mutex_lock (&read_lock);
178 while (read_loop != 0)
180 le = llist_head (list_read);
183 while ((read_loop != 0) && (le != NULL))
185 rf = (read_func_t *) le->value;
187 if (rf->needs_read != TODO)
193 /* We will do this read function */
194 rf->needs_read = ACTIVE;
196 DEBUG ("[thread #%5lu] plugin: plugin_read_thread: Handling %s",
197 (unsigned long int) pthread_self (), le->key);
198 pthread_mutex_unlock (&read_lock);
200 status = rf->callback ();
205 if (rf->wait_time < interval_g)
206 rf->wait_time = interval_g;
207 rf->wait_left = rf->wait_time;
208 rf->wait_time = rf->wait_time * 2;
209 if (rf->wait_time > 86400)
210 rf->wait_time = 86400;
212 NOTICE ("read-function of plugin `%s' "
213 "failed. Will suspend it for %i "
214 "seconds.", le->key, rf->wait_left);
219 rf->wait_time = interval_g;
222 pthread_mutex_lock (&read_lock);
224 rf->needs_read = DONE;
226 } /* while (le != NULL) */
228 if ((read_loop != 0) && (done == 0))
230 DEBUG ("[thread #%5lu] plugin: plugin_read_thread: Waiting on read_cond.",
231 (unsigned long int) pthread_self ());
232 pthread_cond_wait (&read_cond, &read_lock);
234 } /* while (read_loop) */
236 pthread_mutex_unlock (&read_lock);
240 } /* void *plugin_read_thread */
242 static void start_threads (int num)
246 if (read_threads != NULL)
249 read_threads = (pthread_t *) calloc (num, sizeof (pthread_t));
250 if (read_threads == NULL)
252 ERROR ("plugin: start_threads: calloc failed.");
256 read_threads_num = 0;
257 for (i = 0; i < num; i++)
259 if (pthread_create (read_threads + read_threads_num, NULL,
260 plugin_read_thread, NULL) == 0)
266 ERROR ("plugin: start_threads: pthread_create failed.");
270 } /* void start_threads */
272 static void stop_threads (void)
276 pthread_mutex_lock (&read_lock);
278 DEBUG ("plugin: stop_threads: Signalling `read_cond'");
279 pthread_cond_broadcast (&read_cond);
280 pthread_mutex_unlock (&read_lock);
282 for (i = 0; i < read_threads_num; i++)
284 if (pthread_join (read_threads[i], NULL) != 0)
286 ERROR ("plugin: stop_threads: pthread_join failed.");
288 read_threads[i] = (pthread_t) 0;
290 sfree (read_threads);
291 read_threads_num = 0;
292 } /* void stop_threads */
297 void plugin_set_dir (const char *dir)
299 if (plugindir != NULL)
304 else if ((plugindir = strdup (dir)) == NULL)
307 ERROR ("strdup failed: %s",
308 sstrerror (errno, errbuf, sizeof (errbuf)));
313 int plugin_load (const char *type)
317 char filename[BUFSIZE] = "";
318 char typename[BUFSIZE];
324 DEBUG ("type = %s", type);
326 dir = plugin_get_dir ();
329 /* `cpu' should not match `cpufreq'. To solve this we add `.so' to the
330 * type when matching the filename */
331 if (ssnprintf (typename, sizeof (typename),
332 "%s.so", type) >= sizeof (typename))
334 WARNING ("snprintf: truncated: `%s.so'", type);
337 typename_len = strlen (typename);
339 if ((dh = opendir (dir)) == NULL)
342 ERROR ("opendir (%s): %s", dir,
343 sstrerror (errno, errbuf, sizeof (errbuf)));
347 while ((de = readdir (dh)) != NULL)
349 if (strncasecmp (de->d_name, typename, typename_len))
352 if (ssnprintf (filename, sizeof (filename),
353 "%s/%s", dir, de->d_name) >= sizeof (filename))
355 WARNING ("snprintf: truncated: `%s/%s'", dir, de->d_name);
359 if (lstat (filename, &statbuf) == -1)
362 WARNING ("stat %s: %s", filename,
363 sstrerror (errno, errbuf, sizeof (errbuf)));
366 else if (!S_ISREG (statbuf.st_mode))
368 /* don't follow symlinks */
372 if (plugin_load_file (filename) == 0)
380 fprintf (stderr, "Unable to load plugin %s.\n", type);
386 if (filename[0] == '\0')
387 fprintf (stderr, "Could not find plugin %s.\n", type);
393 * The `register_*' functions follow
395 int plugin_register_config (const char *name,
396 int (*callback) (const char *key, const char *val),
397 const char **keys, int keys_num)
399 cf_register (name, callback, keys, keys_num);
401 } /* int plugin_register_config */
403 int plugin_register_complex_config (const char *type,
404 int (*callback) (oconfig_item_t *))
406 return (cf_register_complex (type, callback));
407 } /* int plugin_register_complex_config */
409 int plugin_register_init (const char *name,
410 int (*callback) (void))
412 return (register_callback (&list_init, name, (void *) callback));
413 } /* plugin_register_init */
415 int plugin_register_read (const char *name,
416 int (*callback) (void))
420 rf = (read_func_t *) malloc (sizeof (read_func_t));
424 ERROR ("plugin_register_read: malloc failed: %s",
425 sstrerror (errno, errbuf, sizeof (errbuf)));
429 memset (rf, '\0', sizeof (read_func_t));
430 rf->wait_time = interval_g;
432 rf->callback = callback;
433 rf->needs_read = DONE;
435 return (register_callback (&list_read, name, (void *) rf));
436 } /* int plugin_register_read */
438 int plugin_register_write (const char *name,
439 int (*callback) (const data_set_t *ds, const value_list_t *vl))
441 return (register_callback (&list_write, name, (void *) callback));
442 } /* int plugin_register_write */
444 int plugin_register_flush (const char *name,
445 int (*callback) (const int timeout, const char *identifier))
447 return (register_callback (&list_flush, name, (void *) callback));
448 } /* int plugin_register_flush */
450 int plugin_register_shutdown (char *name,
451 int (*callback) (void))
453 return (register_callback (&list_shutdown, name, (void *) callback));
454 } /* int plugin_register_shutdown */
456 int plugin_register_data_set (const data_set_t *ds)
461 if ((data_sets != NULL)
462 && (c_avl_get (data_sets, ds->type, NULL) == 0))
464 NOTICE ("Replacing DS `%s' with another version.", ds->type);
465 plugin_unregister_data_set (ds->type);
467 else if (data_sets == NULL)
469 data_sets = c_avl_create ((int (*) (const void *, const void *)) strcmp);
470 if (data_sets == NULL)
474 ds_copy = (data_set_t *) malloc (sizeof (data_set_t));
477 memcpy(ds_copy, ds, sizeof (data_set_t));
479 ds_copy->ds = (data_source_t *) malloc (sizeof (data_source_t)
481 if (ds_copy->ds == NULL)
487 for (i = 0; i < ds->ds_num; i++)
488 memcpy (ds_copy->ds + i, ds->ds + i, sizeof (data_source_t));
490 return (c_avl_insert (data_sets, (void *) ds_copy->type, (void *) ds_copy));
491 } /* int plugin_register_data_set */
493 int plugin_register_log (char *name,
494 void (*callback) (int priority, const char *msg))
496 return (register_callback (&list_log, name, (void *) callback));
497 } /* int plugin_register_log */
499 int plugin_register_notification (const char *name,
500 int (*callback) (const notification_t *notif))
502 return (register_callback (&list_notification, name, (void *) callback));
503 } /* int plugin_register_log */
505 int plugin_unregister_config (const char *name)
507 cf_unregister (name);
509 } /* int plugin_unregister_config */
511 int plugin_unregister_complex_config (const char *name)
513 cf_unregister_complex (name);
515 } /* int plugin_unregister_complex_config */
517 int plugin_unregister_init (const char *name)
519 return (plugin_unregister (list_init, name));
522 int plugin_unregister_read (const char *name)
526 e = llist_search (list_read, name);
531 llist_remove (list_read, e);
539 int plugin_unregister_write (const char *name)
541 return (plugin_unregister (list_write, name));
544 int plugin_unregister_flush (const char *name)
546 return (plugin_unregister (list_flush, name));
549 int plugin_unregister_shutdown (const char *name)
551 return (plugin_unregister (list_shutdown, name));
554 int plugin_unregister_data_set (const char *name)
558 if (data_sets == NULL)
561 if (c_avl_remove (data_sets, name, NULL, (void *) &ds) != 0)
568 } /* int plugin_unregister_data_set */
570 int plugin_unregister_log (const char *name)
572 return (plugin_unregister (list_log, name));
575 int plugin_unregister_notification (const char *name)
577 return (plugin_unregister (list_notification, name));
580 void plugin_init_all (void)
582 int (*callback) (void);
586 /* Start read-threads */
587 if (list_read != NULL)
591 rt = global_option_get ("ReadThreads");
593 start_threads ((num > 0) ? num : 5);
596 /* Init the value cache */
599 if (list_init == NULL)
602 le = llist_head (list_init);
605 callback = (int (*) (void)) le->value;
606 status = (*callback) ();
610 ERROR ("Initialization of plugin `%s' "
611 "failed with status %i. "
612 "Plugin will be unloaded.",
614 /* FIXME: Unload _all_ functions */
615 plugin_unregister_read (le->key);
620 } /* void plugin_init_all */
622 void plugin_read_all (void)
629 if (list_read == NULL)
632 pthread_mutex_lock (&read_lock);
634 le = llist_head (list_read);
637 rf = (read_func_t *) le->value;
639 if (rf->needs_read != DONE)
645 if (rf->wait_left > 0)
646 rf->wait_left -= interval_g;
648 if (rf->wait_left <= 0)
650 rf->needs_read = TODO;
656 DEBUG ("plugin: plugin_read_all: Signalling `read_cond'");
657 pthread_cond_broadcast (&read_cond);
658 pthread_mutex_unlock (&read_lock);
659 } /* void plugin_read_all */
661 int plugin_flush_one (int timeout, const char *name)
663 int (*callback) (int);
667 if (list_flush == NULL)
670 le = llist_search (list_flush, name);
673 callback = (int (*) (int)) le->value;
675 status = (*callback) (timeout);
678 } /* int plugin_flush_ont */
680 void plugin_flush_all (int timeout)
682 int (*callback) (int);
685 if (list_flush == NULL)
688 le = llist_head (list_flush);
691 callback = (int (*) (int)) le->value;
694 (*callback) (timeout);
696 } /* void plugin_flush_all */
698 int plugin_flush (const char *plugin, int timeout, const char *identifier)
700 int (*callback) (int timeout, const char *identifier);
703 if (list_flush == NULL)
706 le = llist_head (list_flush);
710 && (strcmp (plugin, le->key) != 0))
713 callback = (int (*) (int, const char *)) le->value;
716 (*callback) (timeout, identifier);
718 } /* int plugin_flush */
720 void plugin_shutdown_all (void)
722 int (*callback) (void);
727 if (list_shutdown == NULL)
730 le = llist_head (list_shutdown);
733 callback = (int (*) (void)) le->value;
735 /* Advance the pointer before calling the callback allows
736 * shutdown functions to unregister themselves. If done the
737 * other way around the memory `le' points to will be freed
738 * after callback returns. */
743 } /* void plugin_shutdown_all */
745 int plugin_dispatch_values (value_list_t *vl)
747 int (*callback) (const data_set_t *, const value_list_t *);
751 if ((vl == NULL) || (*vl->type == '\0')) {
752 ERROR ("plugin_dispatch_values: Invalid value list.");
756 if (list_write == NULL)
758 ERROR ("plugin_dispatch_values: No write callback has been "
759 "registered. Please load at least one plugin "
760 "that provides a write function.");
764 if (data_sets == NULL)
766 ERROR ("plugin_dispatch_values: No data sets registered. "
767 "Could the types database be read? Check "
768 "your `TypesDB' setting!");
772 if (c_avl_get (data_sets, vl->type, (void *) &ds) != 0)
774 INFO ("plugin_dispatch_values: Dataset not found: %s", vl->type);
778 DEBUG ("plugin_dispatch_values: time = %u; interval = %i; "
780 "plugin = %s; plugin_instance = %s; "
781 "type = %s; type_instance = %s;",
782 (unsigned int) vl->time, vl->interval,
784 vl->plugin, vl->plugin_instance,
785 vl->type, vl->type_instance);
788 assert (0 == strcmp (ds->type, vl->type));
790 if (0 != strcmp (ds->type, vl->type))
791 WARNING ("plugin_dispatch_values: (ds->type = %s) != (vl->type = %s)",
796 assert (ds->ds_num == vl->values_len);
798 if (ds->ds_num != vl->values_len)
800 ERROR ("plugin_dispatch_values: ds->type = %s: "
801 "(ds->ds_num = %i) != "
802 "(vl->values_len = %i)",
803 ds->type, ds->ds_num, vl->values_len);
808 escape_slashes (vl->host, sizeof (vl->host));
809 escape_slashes (vl->plugin, sizeof (vl->plugin));
810 escape_slashes (vl->plugin_instance, sizeof (vl->plugin_instance));
811 escape_slashes (vl->type, sizeof (vl->type));
812 escape_slashes (vl->type_instance, sizeof (vl->type_instance));
814 /* Update the value cache */
816 ut_check_threshold (ds, vl);
818 le = llist_head (list_write);
821 callback = (int (*) (const data_set_t *, const value_list_t *)) le->value;
822 (*callback) (ds, vl);
828 } /* int plugin_dispatch_values */
830 int plugin_dispatch_notification (const notification_t *notif)
832 int (*callback) (const notification_t *);
834 /* Possible TODO: Add flap detection here */
836 DEBUG ("plugin_dispatch_notification: severity = %i; message = %s; "
837 "time = %u; host = %s;",
838 notif->severity, notif->message,
839 (unsigned int) notif->time, notif->host);
841 /* Nobody cares for notifications */
842 if (list_notification == NULL)
845 le = llist_head (list_notification);
848 callback = (int (*) (const notification_t *)) le->value;
855 } /* int plugin_dispatch_notification */
857 void plugin_log (int level, const char *format, ...)
862 void (*callback) (int, const char *);
865 if (list_log == NULL)
869 if (level >= LOG_DEBUG)
873 va_start (ap, format);
874 vsnprintf (msg, 512, format, ap);
878 le = llist_head (list_log);
881 callback = (void (*) (int, const char *)) le->value;
882 (*callback) (level, msg);
886 } /* void plugin_log */
888 const data_set_t *plugin_get_ds (const char *name)
892 if (c_avl_get (data_sets, name, (void *) &ds) != 0)
894 DEBUG ("No such dataset registered: %s", name);
899 } /* data_set_t *plugin_get_ds */