1 /**
2 * collectd - src/daemon/plugin.h
3 * Copyright (C) 2005-2014 Florian octo Forster
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Florian octo Forster <octo at collectd.org>
25 * Sebastian Harl <sh at tokkee.org>
26 **/
28 #ifndef PLUGIN_H
29 #define PLUGIN_H
31 #include "collectd.h"
33 #include "configfile.h"
34 #include "meta_data.h"
35 #include "utils_time.h"
37 #include <pthread.h>
39 #define PLUGIN_FLAGS_GLOBAL 0x0001
41 #ifndef DATA_MAX_NAME_LEN
42 # define DATA_MAX_NAME_LEN 128
43 #endif
45 #define DS_TYPE_COUNTER 0
46 #define DS_TYPE_GAUGE 1
47 #define DS_TYPE_DERIVE 2
48 #define DS_TYPE_ABSOLUTE 3
50 #define DS_TYPE_TO_STRING(t) (t == DS_TYPE_COUNTER) ? "counter" : \
51 (t == DS_TYPE_GAUGE) ? "gauge" : \
52 (t == DS_TYPE_DERIVE) ? "derive" : \
53 (t == DS_TYPE_ABSOLUTE) ? "absolute" : \
54 "unknown"
57 #ifndef LOG_ERR
58 # define LOG_ERR 3
59 #endif
60 #ifndef LOG_WARNING
61 # define LOG_WARNING 4
62 #endif
63 #ifndef LOG_NOTICE
64 # define LOG_NOTICE 5
65 #endif
66 #ifndef LOG_INFO
67 # define LOG_INFO 6
68 #endif
69 #ifndef LOG_DEBUG
70 # define LOG_DEBUG 7
71 #endif
73 #define NOTIF_MAX_MSG_LEN 256
75 #define NOTIF_FAILURE 1
76 #define NOTIF_WARNING 2
77 #define NOTIF_OKAY 4
79 #define plugin_interval (plugin_get_ctx().interval)
81 /*
82 * Public data types
83 */
84 struct identifier_s
85 {
86 char *host;
87 char *plugin;
88 char *plugin_instance;
89 char *type;
90 char *type_instance;
91 };
92 typedef struct identifier_s identifier_t;
94 typedef unsigned long long counter_t;
95 typedef double gauge_t;
96 typedef int64_t derive_t;
97 typedef uint64_t absolute_t;
99 union value_u
100 {
101 counter_t counter;
102 gauge_t gauge;
103 derive_t derive;
104 absolute_t absolute;
105 };
106 typedef union value_u value_t;
108 struct value_list_s
109 {
110 value_t *values;
111 size_t values_len;
112 cdtime_t time;
113 cdtime_t interval;
114 char host[DATA_MAX_NAME_LEN];
115 char plugin[DATA_MAX_NAME_LEN];
116 char plugin_instance[DATA_MAX_NAME_LEN];
117 char type[DATA_MAX_NAME_LEN];
118 char type_instance[DATA_MAX_NAME_LEN];
119 meta_data_t *meta;
120 };
121 typedef struct value_list_s value_list_t;
123 #define VALUE_LIST_INIT { .values = NULL, .meta = NULL }
125 struct data_source_s
126 {
127 char name[DATA_MAX_NAME_LEN];
128 int type;
129 double min;
130 double max;
131 };
132 typedef struct data_source_s data_source_t;
134 struct data_set_s
135 {
136 char type[DATA_MAX_NAME_LEN];
137 size_t ds_num;
138 data_source_t *ds;
139 };
140 typedef struct data_set_s data_set_t;
142 enum notification_meta_type_e
143 {
144 NM_TYPE_STRING,
145 NM_TYPE_SIGNED_INT,
146 NM_TYPE_UNSIGNED_INT,
147 NM_TYPE_DOUBLE,
148 NM_TYPE_BOOLEAN
149 };
151 typedef struct notification_meta_s
152 {
153 char name[DATA_MAX_NAME_LEN];
154 enum notification_meta_type_e type;
155 union
156 {
157 const char *nm_string;
158 int64_t nm_signed_int;
159 uint64_t nm_unsigned_int;
160 double nm_double;
161 _Bool nm_boolean;
162 } nm_value;
163 struct notification_meta_s *next;
164 } notification_meta_t;
166 typedef struct notification_s
167 {
168 int severity;
169 cdtime_t time;
170 char message[NOTIF_MAX_MSG_LEN];
171 char host[DATA_MAX_NAME_LEN];
172 char plugin[DATA_MAX_NAME_LEN];
173 char plugin_instance[DATA_MAX_NAME_LEN];
174 char type[DATA_MAX_NAME_LEN];
175 char type_instance[DATA_MAX_NAME_LEN];
176 notification_meta_t *meta;
177 } notification_t;
179 struct user_data_s
180 {
181 void *data;
182 void (*free_func) (void *);
183 };
184 typedef struct user_data_s user_data_t;
186 struct plugin_ctx_s
187 {
188 cdtime_t interval;
189 cdtime_t flush_interval;
190 cdtime_t flush_timeout;
191 };
192 typedef struct plugin_ctx_s plugin_ctx_t;
194 /*
195 * Callback types
196 */
197 typedef int (*plugin_init_cb) (void);
198 typedef int (*plugin_read_cb) (user_data_t *);
199 typedef int (*plugin_write_cb) (const data_set_t *, const value_list_t *,
200 user_data_t *);
201 typedef int (*plugin_flush_cb) (cdtime_t timeout, const char *identifier,
202 user_data_t *);
203 /* "missing" callback. Returns less than zero on failure, zero if other
204 * callbacks should be called, greater than zero if no more callbacks should be
205 * called. */
206 typedef int (*plugin_missing_cb) (const value_list_t *, user_data_t *);
207 typedef void (*plugin_log_cb) (int severity, const char *message,
208 user_data_t *);
209 typedef int (*plugin_shutdown_cb) (void);
210 typedef int (*plugin_notification_cb) (const notification_t *,
211 user_data_t *);
212 /*
213 * NAME
214 * plugin_set_dir
215 *
216 * DESCRIPTION
217 * Sets the current `plugindir'
218 *
219 * ARGUMENTS
220 * `dir' Path to the plugin directory
221 *
222 * NOTES
223 * If `dir' is NULL the compiled in default `PLUGINDIR' is used.
224 */
225 void plugin_set_dir (const char *dir);
227 /*
228 * NAME
229 * plugin_load
230 *
231 * DESCRIPTION
232 * Searches the current `plugindir' (see `plugin_set_dir') for the plugin
233 * named $type and loads it. Afterwards the plugin's `module_register'
234 * function is called, which then calls `plugin_register' to register callback
235 * functions.
236 *
237 * ARGUMENTS
238 * `name' Name of the plugin to load.
239 * `flags' Hints on how to handle this plugin.
240 *
241 * RETURN VALUE
242 * Returns zero upon success, a value greater than zero if no plugin was found
243 * and a value below zero if an error occurs.
244 *
245 * NOTES
246 * Re-loading an already loaded module is detected and zero is returned in
247 * this case.
248 */
249 int plugin_load (const char *name, uint32_t flags);
251 int plugin_init_all (void);
252 void plugin_read_all (void);
253 int plugin_read_all_once (void);
254 int plugin_shutdown_all (void);
256 /*
257 * NAME
258 * plugin_write
259 *
260 * DESCRIPTION
261 * Calls the write function of the given plugin with the provided data set and
262 * value list. It differs from `plugin_dispatch_value' in that it does not
263 * update the cache, does not do threshold checking, call the chain subsystem
264 * and so on. It looks up the requested plugin and invokes the function, end
265 * of story.
266 *
267 * ARGUMENTS
268 * plugin Name of the plugin. If NULL, the value is sent to all registered
269 * write functions.
270 * ds Pointer to the data_set_t structure. If NULL, the data set is
271 * looked up according to the `type' member in the `vl' argument.
272 * vl The actual value to be processed. Must not be NULL.
273 *
274 * RETURN VALUE
275 * Returns zero upon success or non-zero if an error occurred. If `plugin' is
276 * NULL and more than one plugin is called, an error is only returned if *all*
277 * plugins fail.
278 *
279 * NOTES
280 * This is the function used by the `write' built-in target. May be used by
281 * other target plugins.
282 */
283 int plugin_write (const char *plugin,
284 const data_set_t *ds, const value_list_t *vl);
286 int plugin_flush (const char *plugin, cdtime_t timeout, const char *identifier);
288 /*
289 * The `plugin_register_*' functions are used to make `config', `init',
290 * `read', `write' and `shutdown' functions known to the plugin
291 * infrastructure. Also, the data-formats are made public like this.
292 */
293 int plugin_register_config (const char *name,
294 int (*callback) (const char *key, const char *val),
295 const char **keys, int keys_num);
296 int plugin_register_complex_config (const char *type,
297 int (*callback) (oconfig_item_t *));
298 int plugin_register_init (const char *name,
299 plugin_init_cb callback);
300 int plugin_register_read (const char *name,
301 int (*callback) (void));
302 /* "user_data" will be freed automatically, unless
303 * "plugin_register_complex_read" returns an error (non-zero). */
304 int plugin_register_complex_read (const char *group, const char *name,
305 plugin_read_cb callback,
306 cdtime_t interval,
307 user_data_t const *user_data);
308 int plugin_register_write (const char *name,
309 plugin_write_cb callback, user_data_t const *user_data);
310 int plugin_register_flush (const char *name,
311 plugin_flush_cb callback, user_data_t const *user_data);
312 int plugin_register_missing (const char *name,
313 plugin_missing_cb callback, user_data_t const *user_data);
314 int plugin_register_shutdown (const char *name,
315 plugin_shutdown_cb callback);
316 int plugin_register_data_set (const data_set_t *ds);
317 int plugin_register_log (const char *name,
318 plugin_log_cb callback, user_data_t const *user_data);
319 int plugin_register_notification (const char *name,
320 plugin_notification_cb callback, user_data_t const *user_data);
322 int plugin_unregister_config (const char *name);
323 int plugin_unregister_complex_config (const char *name);
324 int plugin_unregister_init (const char *name);
325 int plugin_unregister_read (const char *name);
326 int plugin_unregister_read_group (const char *group);
327 int plugin_unregister_write (const char *name);
328 int plugin_unregister_flush (const char *name);
329 int plugin_unregister_missing (const char *name);
330 int plugin_unregister_shutdown (const char *name);
331 int plugin_unregister_data_set (const char *name);
332 int plugin_unregister_log (const char *name);
333 int plugin_unregister_notification (const char *name);
335 /*
336 * NAME
337 * plugin_log_available_writers
338 *
339 * DESCRIPTION
340 * This function can be called to output a list of _all_ registered
341 * writers to the logfacility.
342 * Since some writers dynamically build their name it can be hard for
343 * the configuring person to know it. This function will fill this gap.
344 */
345 void plugin_log_available_writers (void);
347 /*
348 * NAME
349 * plugin_dispatch_values
350 *
351 * DESCRIPTION
352 * This function is called by reading processes with the values they've
353 * aquired. The function fetches the data-set definition (that has been
354 * registered using `plugin_register_data_set') and calls _all_ registered
355 * write-functions.
356 *
357 * ARGUMENTS
358 * `vl' Value list of the values that have been read by a `read'
359 * function.
360 */
361 int plugin_dispatch_values (value_list_t const *vl);
363 /*
364 * NAME
365 * plugin_dispatch_multivalue
366 *
367 * SYNOPSIS
368 * plugin_dispatch_multivalue (vl, 1, DS_TYPE_GAUGE,
369 * "free", 42.0,
370 * "used", 58.0,
371 * NULL);
372 *
373 * DESCRIPTION
374 * Takes a list of type instances and values and dispatches that in a batch,
375 * making sure that all values have the same time stamp. If "store_percentage"
376 * is set to true, the "type" is set to "percent" and a percentage is
377 * calculated and dispatched, rather than the absolute values. Values that are
378 * NaN are dispatched as NaN and will not influence the total.
379 *
380 * The variadic arguments is a list of type_instance / type pairs, that are
381 * interpreted as type "char const *" and type, encoded by their corresponding
382 * "store_type":
383 *
384 * - "gauge_t" when "DS_TYPE_GAUGE"
385 * - "absolute_t" when "DS_TYPE_ABSOLUTE"
386 * - "derive_t" when "DS_TYPE_DERIVE"
387 * - "counter_t" when "DS_TYPE_COUNTER"
388 *
389 * The last argument must be
390 * a NULL pointer to signal end-of-list.
391 *
392 * RETURNS
393 * The number of values it failed to dispatch (zero on success).
394 */
395 __attribute__((sentinel))
396 int plugin_dispatch_multivalue (value_list_t const *vl,
397 _Bool store_percentage, int store_type, ...);
399 int plugin_dispatch_missing (const value_list_t *vl);
401 int plugin_dispatch_notification (const notification_t *notif);
403 void plugin_log (int level, const char *format, ...)
404 __attribute__ ((format(printf,2,3)));
406 /* These functions return the parsed severity or less than zero on failure. */
407 int parse_log_severity (const char *severity);
408 int parse_notif_severity (const char *severity);
410 #define ERROR(...) plugin_log (LOG_ERR, __VA_ARGS__)
411 #define WARNING(...) plugin_log (LOG_WARNING, __VA_ARGS__)
412 #define NOTICE(...) plugin_log (LOG_NOTICE, __VA_ARGS__)
413 #define INFO(...) plugin_log (LOG_INFO, __VA_ARGS__)
414 #if COLLECT_DEBUG
415 # define DEBUG(...) plugin_log (LOG_DEBUG, __VA_ARGS__)
416 #else /* COLLECT_DEBUG */
417 # define DEBUG(...) /* noop */
418 #endif /* ! COLLECT_DEBUG */
420 const data_set_t *plugin_get_ds (const char *name);
422 int plugin_notification_meta_add_string (notification_t *n,
423 const char *name,
424 const char *value);
425 int plugin_notification_meta_add_signed_int (notification_t *n,
426 const char *name,
427 int64_t value);
428 int plugin_notification_meta_add_unsigned_int (notification_t *n,
429 const char *name,
430 uint64_t value);
431 int plugin_notification_meta_add_double (notification_t *n,
432 const char *name,
433 double value);
434 int plugin_notification_meta_add_boolean (notification_t *n,
435 const char *name,
436 _Bool value);
438 int plugin_notification_meta_copy (notification_t *dst,
439 const notification_t *src);
441 int plugin_notification_meta_free (notification_meta_t *n);
443 /*
444 * Plugin context management.
445 */
447 void plugin_init_ctx (void);
449 plugin_ctx_t plugin_get_ctx (void);
450 plugin_ctx_t plugin_set_ctx (plugin_ctx_t ctx);
452 /*
453 * NAME
454 * plugin_get_interval
455 *
456 * DESCRIPTION
457 * This function returns the current value of the plugin's interval. The
458 * return value will be strictly greater than zero in all cases. If
459 * everything else fails, it will fall back to 10 seconds.
460 */
461 cdtime_t plugin_get_interval (void);
463 /*
464 * Context-aware thread management.
465 */
467 int plugin_thread_create (pthread_t *thread, const pthread_attr_t *attr,
468 void *(*start_routine) (void *), void *arg, char const *name);
470 /*
471 * Plugins need to implement this
472 */
474 void module_register (void);
476 #endif /* PLUGIN_H */