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 (%s) failed: %s", file, error);
152 fprintf (stderr, "lt_dlopen (%s) failed: %s\n", file, 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 (snprintf (typename, BUFSIZE, "%s.so", type) >= BUFSIZE)
333 WARNING ("snprintf: truncated: `%s.so'", type);
336 typename_len = strlen (typename);
338 if ((dh = opendir (dir)) == NULL)
341 ERROR ("opendir (%s): %s", dir,
342 sstrerror (errno, errbuf, sizeof (errbuf)));
346 while ((de = readdir (dh)) != NULL)
348 if (strncasecmp (de->d_name, typename, typename_len))
351 if (snprintf (filename, BUFSIZE, "%s/%s", dir, de->d_name) >= BUFSIZE)
353 WARNING ("snprintf: truncated: `%s/%s'", dir, de->d_name);
357 if (lstat (filename, &statbuf) == -1)
360 WARNING ("stat %s: %s", filename,
361 sstrerror (errno, errbuf, sizeof (errbuf)));
364 else if (!S_ISREG (statbuf.st_mode))
366 /* don't follow symlinks */
370 if (plugin_load_file (filename) == 0)
378 fprintf (stderr, "Unable to load plugin %s.\n", type);
384 if (filename[0] == '\0')
385 fprintf (stderr, "Could not find plugin %s.\n", type);
391 * The `register_*' functions follow
393 int plugin_register_config (const char *name,
394 int (*callback) (const char *key, const char *val),
395 const char **keys, int keys_num)
397 cf_register (name, callback, keys, keys_num);
399 } /* int plugin_register_config */
401 int plugin_register_complex_config (const char *type,
402 int (*callback) (oconfig_item_t *))
404 return (cf_register_complex (type, callback));
405 } /* int plugin_register_complex_config */
407 int plugin_register_init (const char *name,
408 int (*callback) (void))
410 return (register_callback (&list_init, name, (void *) callback));
411 } /* plugin_register_init */
413 int plugin_register_read (const char *name,
414 int (*callback) (void))
418 rf = (read_func_t *) malloc (sizeof (read_func_t));
422 ERROR ("plugin_register_read: malloc failed: %s",
423 sstrerror (errno, errbuf, sizeof (errbuf)));
427 memset (rf, '\0', sizeof (read_func_t));
428 rf->wait_time = interval_g;
430 rf->callback = callback;
431 rf->needs_read = DONE;
433 return (register_callback (&list_read, name, (void *) rf));
434 } /* int plugin_register_read */
436 int plugin_register_write (const char *name,
437 int (*callback) (const data_set_t *ds, const value_list_t *vl))
439 return (register_callback (&list_write, name, (void *) callback));
440 } /* int plugin_register_write */
442 int plugin_register_flush (const char *name, int (*callback) (const int))
444 return (register_callback (&list_flush, name, (void *) callback));
445 } /* int plugin_register_flush */
447 int plugin_register_shutdown (char *name,
448 int (*callback) (void))
450 return (register_callback (&list_shutdown, name, (void *) callback));
451 } /* int plugin_register_shutdown */
453 int plugin_register_data_set (const data_set_t *ds)
458 if ((data_sets != NULL)
459 && (c_avl_get (data_sets, ds->type, NULL) == 0))
461 NOTICE ("Replacing DS `%s' with another version.", ds->type);
462 plugin_unregister_data_set (ds->type);
464 else if (data_sets == NULL)
466 data_sets = c_avl_create ((int (*) (const void *, const void *)) strcmp);
467 if (data_sets == NULL)
471 ds_copy = (data_set_t *) malloc (sizeof (data_set_t));
474 memcpy(ds_copy, ds, sizeof (data_set_t));
476 ds_copy->ds = (data_source_t *) malloc (sizeof (data_source_t)
478 if (ds_copy->ds == NULL)
484 for (i = 0; i < ds->ds_num; i++)
485 memcpy (ds_copy->ds + i, ds->ds + i, sizeof (data_source_t));
487 return (c_avl_insert (data_sets, (void *) ds_copy->type, (void *) ds_copy));
488 } /* int plugin_register_data_set */
490 int plugin_register_log (char *name,
491 void (*callback) (int priority, const char *msg))
493 return (register_callback (&list_log, name, (void *) callback));
494 } /* int plugin_register_log */
496 int plugin_register_notification (const char *name,
497 int (*callback) (const notification_t *notif))
499 return (register_callback (&list_notification, name, (void *) callback));
500 } /* int plugin_register_log */
502 int plugin_unregister_config (const char *name)
504 cf_unregister (name);
506 } /* int plugin_unregister_config */
508 int plugin_unregister_complex_config (const char *name)
510 cf_unregister_complex (name);
512 } /* int plugin_unregister_complex_config */
514 int plugin_unregister_init (const char *name)
516 return (plugin_unregister (list_init, name));
519 int plugin_unregister_read (const char *name)
523 e = llist_search (list_read, name);
528 llist_remove (list_read, e);
536 int plugin_unregister_write (const char *name)
538 return (plugin_unregister (list_write, name));
541 int plugin_unregister_flush (const char *name)
543 return (plugin_unregister (list_flush, name));
546 int plugin_unregister_shutdown (const char *name)
548 return (plugin_unregister (list_shutdown, name));
551 int plugin_unregister_data_set (const char *name)
555 if (data_sets == NULL)
558 if (c_avl_remove (data_sets, name, NULL, (void *) &ds) != 0)
565 } /* int plugin_unregister_data_set */
567 int plugin_unregister_log (const char *name)
569 return (plugin_unregister (list_log, name));
572 int plugin_unregister_notification (const char *name)
574 return (plugin_unregister (list_notification, name));
577 void plugin_init_all (void)
579 int (*callback) (void);
583 /* Init the value cache */
586 if ((list_init == NULL) && (list_read == NULL))
589 /* Calling all init callbacks before checking if read callbacks
590 * are available allows the init callbacks to register the read
592 le = llist_head (list_init);
595 callback = (int (*) (void)) le->value;
596 status = (*callback) ();
600 ERROR ("Initialization of plugin `%s' "
601 "failed with status %i. "
602 "Plugin will be unloaded.",
604 /* Plugins that register read callbacks from the init
605 * callback should take care of appropriate error
606 * handling themselves. */
607 /* FIXME: Unload _all_ functions */
608 plugin_unregister_read (le->key);
614 /* Start read-threads */
615 if (list_read != NULL)
619 rt = global_option_get ("ReadThreads");
621 start_threads ((num > 0) ? num : 5);
623 } /* void plugin_init_all */
625 void plugin_read_all (void)
632 if (list_read == NULL)
635 pthread_mutex_lock (&read_lock);
637 le = llist_head (list_read);
640 rf = (read_func_t *) le->value;
642 if (rf->needs_read != DONE)
648 if (rf->wait_left > 0)
649 rf->wait_left -= interval_g;
651 if (rf->wait_left <= 0)
653 rf->needs_read = TODO;
659 DEBUG ("plugin: plugin_read_all: Signalling `read_cond'");
660 pthread_cond_broadcast (&read_cond);
661 pthread_mutex_unlock (&read_lock);
662 } /* void plugin_read_all */
664 int plugin_flush_one (int timeout, const char *name)
666 int (*callback) (int);
670 if (list_flush == NULL)
673 le = llist_search (list_flush, name);
676 callback = (int (*) (int)) le->value;
678 status = (*callback) (timeout);
681 } /* int plugin_flush_ont */
683 void plugin_flush_all (int timeout)
685 int (*callback) (int);
688 if (list_flush == NULL)
691 le = llist_head (list_flush);
694 callback = (int (*) (int)) le->value;
697 (*callback) (timeout);
699 } /* void plugin_flush_all */
701 void plugin_shutdown_all (void)
703 int (*callback) (void);
708 if (list_shutdown == NULL)
711 le = llist_head (list_shutdown);
714 callback = (int (*) (void)) le->value;
716 /* Advance the pointer before calling the callback allows
717 * shutdown functions to unregister themselves. If done the
718 * other way around the memory `le' points to will be freed
719 * after callback returns. */
724 } /* void plugin_shutdown_all */
726 int plugin_dispatch_values (const char *name, value_list_t *vl)
728 int (*callback) (const data_set_t *, const value_list_t *);
732 if (list_write == NULL)
734 ERROR ("plugin_dispatch_values: No write callback has been "
735 "registered. Please load at least one plugin "
736 "that provides a write function.");
740 if (data_sets == NULL)
742 ERROR ("plugin_dispatch_values: No data sets registered. "
743 "Could the types database be read? Check "
744 "your `TypesDB' setting!");
748 if (c_avl_get (data_sets, name, (void *) &ds) != 0)
750 INFO ("plugin_dispatch_values: Dataset not found: %s", name);
754 DEBUG ("plugin_dispatch_values: time = %u; interval = %i; "
756 "plugin = %s; plugin_instance = %s; "
757 "type = %s; type_instance = %s;",
758 (unsigned int) vl->time, vl->interval,
760 vl->plugin, vl->plugin_instance,
761 ds->type, vl->type_instance);
764 assert (ds->ds_num == vl->values_len);
766 if (ds->ds_num != vl->values_len)
768 ERROR ("plugin_dispatch_values: ds->type = %s: "
769 "(ds->ds_num = %i) != "
770 "(vl->values_len = %i)",
771 ds->type, ds->ds_num, vl->values_len);
776 escape_slashes (vl->host, sizeof (vl->host));
777 escape_slashes (vl->plugin, sizeof (vl->plugin));
778 escape_slashes (vl->plugin_instance, sizeof (vl->plugin_instance));
779 escape_slashes (vl->type_instance, sizeof (vl->type_instance));
781 /* Update the value cache */
783 ut_check_threshold (ds, vl);
785 le = llist_head (list_write);
788 callback = (int (*) (const data_set_t *, const value_list_t *)) le->value;
789 (*callback) (ds, vl);
795 } /* int plugin_dispatch_values */
797 int plugin_dispatch_notification (const notification_t *notif)
799 int (*callback) (const notification_t *);
801 /* Possible TODO: Add flap detection here */
803 DEBUG ("plugin_dispatch_notification: severity = %i; message = %s; "
804 "time = %u; host = %s;",
805 notif->severity, notif->message,
806 (unsigned int) notif->time, notif->host);
808 /* Nobody cares for notifications */
809 if (list_notification == NULL)
812 le = llist_head (list_notification);
815 callback = (int (*) (const notification_t *)) le->value;
822 } /* int plugin_dispatch_notification */
824 void plugin_log (int level, const char *format, ...)
829 void (*callback) (int, const char *);
832 if (list_log == NULL)
836 if (level >= LOG_DEBUG)
840 va_start (ap, format);
841 vsnprintf (msg, sizeof (msg), format, ap);
842 msg[sizeof (msg) - 1] = '\0';
845 le = llist_head (list_log);
848 callback = (void (*) (int, const char *)) le->value;
849 (*callback) (level, msg);
853 } /* void plugin_log */
855 const data_set_t *plugin_get_ds (const char *name)
859 if (c_avl_get (data_sets, name, (void *) &ds) != 0)
861 DEBUG ("No such dataset registered: %s", name);
866 } /* data_set_t *plugin_get_ds */