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) \
51 (t == DS_TYPE_COUNTER) ? "counter" : (t == DS_TYPE_GAUGE) \
52 ? "gauge" \
53 : (t == DS_TYPE_DERIVE) \
54 ? "derive" \
55 : (t == DS_TYPE_ABSOLUTE) \
56 ? "absolute" \
57 : "unknown"
59 #ifndef LOG_ERR
60 #define LOG_ERR 3
61 #endif
62 #ifndef LOG_WARNING
63 #define LOG_WARNING 4
64 #endif
65 #ifndef LOG_NOTICE
66 #define LOG_NOTICE 5
67 #endif
68 #ifndef LOG_INFO
69 #define LOG_INFO 6
70 #endif
71 #ifndef LOG_DEBUG
72 #define LOG_DEBUG 7
73 #endif
75 #define NOTIF_MAX_MSG_LEN 256
77 #define NOTIF_FAILURE 1
78 #define NOTIF_WARNING 2
79 #define NOTIF_OKAY 4
81 #define plugin_interval (plugin_get_ctx().interval)
83 /*
84 * Public data types
85 */
86 struct identifier_s {
87 char *host;
88 char *plugin;
89 char *plugin_instance;
90 char *type;
91 char *type_instance;
92 };
93 typedef struct identifier_s identifier_t;
95 typedef unsigned long long counter_t;
96 typedef double gauge_t;
97 typedef int64_t derive_t;
98 typedef uint64_t absolute_t;
100 union value_u {
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 value_t *values;
110 size_t values_len;
111 cdtime_t time;
112 cdtime_t interval;
113 char host[DATA_MAX_NAME_LEN];
114 char plugin[DATA_MAX_NAME_LEN];
115 char plugin_instance[DATA_MAX_NAME_LEN];
116 char type[DATA_MAX_NAME_LEN];
117 char type_instance[DATA_MAX_NAME_LEN];
118 meta_data_t *meta;
119 };
120 typedef struct value_list_s value_list_t;
122 #define VALUE_LIST_INIT \
123 { .values = NULL, .meta = NULL }
125 struct data_source_s {
126 char name[DATA_MAX_NAME_LEN];
127 int type;
128 double min;
129 double max;
130 };
131 typedef struct data_source_s data_source_t;
133 struct data_set_s {
134 char type[DATA_MAX_NAME_LEN];
135 size_t ds_num;
136 data_source_t *ds;
137 };
138 typedef struct data_set_s data_set_t;
140 enum notification_meta_type_e {
141 NM_TYPE_STRING,
142 NM_TYPE_SIGNED_INT,
143 NM_TYPE_UNSIGNED_INT,
144 NM_TYPE_DOUBLE,
145 NM_TYPE_BOOLEAN
146 };
148 typedef struct notification_meta_s {
149 char name[DATA_MAX_NAME_LEN];
150 enum notification_meta_type_e type;
151 union {
152 const char *nm_string;
153 int64_t nm_signed_int;
154 uint64_t nm_unsigned_int;
155 double nm_double;
156 _Bool nm_boolean;
157 } nm_value;
158 struct notification_meta_s *next;
159 } notification_meta_t;
161 typedef struct notification_s {
162 int severity;
163 cdtime_t time;
164 char message[NOTIF_MAX_MSG_LEN];
165 char host[DATA_MAX_NAME_LEN];
166 char plugin[DATA_MAX_NAME_LEN];
167 char plugin_instance[DATA_MAX_NAME_LEN];
168 char type[DATA_MAX_NAME_LEN];
169 char type_instance[DATA_MAX_NAME_LEN];
170 notification_meta_t *meta;
171 } notification_t;
173 struct user_data_s {
174 void *data;
175 void (*free_func)(void *);
176 };
177 typedef struct user_data_s user_data_t;
179 struct plugin_ctx_s {
180 cdtime_t interval;
181 cdtime_t flush_interval;
182 cdtime_t flush_timeout;
183 };
184 typedef struct plugin_ctx_s plugin_ctx_t;
186 /*
187 * Callback types
188 */
189 typedef int (*plugin_init_cb)(void);
190 typedef int (*plugin_read_cb)(user_data_t *);
191 typedef int (*plugin_write_cb)(const data_set_t *, const value_list_t *,
192 user_data_t *);
193 typedef int (*plugin_flush_cb)(cdtime_t timeout, const char *identifier,
194 user_data_t *);
195 /* "missing" callback. Returns less than zero on failure, zero if other
196 * callbacks should be called, greater than zero if no more callbacks should be
197 * called. */
198 typedef int (*plugin_missing_cb)(const value_list_t *, user_data_t *);
199 typedef void (*plugin_log_cb)(int severity, const char *message, user_data_t *);
200 typedef int (*plugin_shutdown_cb)(void);
201 typedef int (*plugin_notification_cb)(const notification_t *, user_data_t *);
202 /*
203 * NAME
204 * plugin_set_dir
205 *
206 * DESCRIPTION
207 * Sets the current `plugindir'
208 *
209 * ARGUMENTS
210 * `dir' Path to the plugin directory
211 *
212 * NOTES
213 * If `dir' is NULL the compiled in default `PLUGINDIR' is used.
214 */
215 void plugin_set_dir(const char *dir);
217 /*
218 * NAME
219 * plugin_load
220 *
221 * DESCRIPTION
222 * Searches the current `plugindir' (see `plugin_set_dir') for the plugin
223 * named $type and loads it. Afterwards the plugin's `module_register'
224 * function is called, which then calls `plugin_register' to register callback
225 * functions.
226 *
227 * ARGUMENTS
228 * `name' Name of the plugin to load.
229 * `flags' Hints on how to handle this plugin.
230 *
231 * RETURN VALUE
232 * Returns zero upon success, a value greater than zero if no plugin was found
233 * and a value below zero if an error occurs.
234 *
235 * NOTES
236 * Re-loading an already loaded module is detected and zero is returned in
237 * this case.
238 */
239 int plugin_load(const char *name, uint32_t flags);
241 int plugin_init_all(void);
242 void plugin_read_all(void);
243 int plugin_read_all_once(void);
244 int plugin_shutdown_all(void);
246 /*
247 * NAME
248 * plugin_write
249 *
250 * DESCRIPTION
251 * Calls the write function of the given plugin with the provided data set and
252 * value list. It differs from `plugin_dispatch_value' in that it does not
253 * update the cache, does not do threshold checking, call the chain subsystem
254 * and so on. It looks up the requested plugin and invokes the function, end
255 * of story.
256 *
257 * ARGUMENTS
258 * plugin Name of the plugin. If NULL, the value is sent to all registered
259 * write functions.
260 * ds Pointer to the data_set_t structure. If NULL, the data set is
261 * looked up according to the `type' member in the `vl' argument.
262 * vl The actual value to be processed. Must not be NULL.
263 *
264 * RETURN VALUE
265 * Returns zero upon success or non-zero if an error occurred. If `plugin' is
266 * NULL and more than one plugin is called, an error is only returned if *all*
267 * plugins fail.
268 *
269 * NOTES
270 * This is the function used by the `write' built-in target. May be used by
271 * other target plugins.
272 */
273 int plugin_write(const char *plugin, const data_set_t *ds,
274 const value_list_t *vl);
276 int plugin_flush(const char *plugin, cdtime_t timeout, const char *identifier);
278 /*
279 * The `plugin_register_*' functions are used to make `config', `init',
280 * `read', `write' and `shutdown' functions known to the plugin
281 * infrastructure. Also, the data-formats are made public like this.
282 */
283 int plugin_register_config(const char *name,
284 int (*callback)(const char *key, const char *val),
285 const char **keys, int keys_num);
286 int plugin_register_complex_config(const char *type,
287 int (*callback)(oconfig_item_t *));
288 int plugin_register_init(const char *name, plugin_init_cb callback);
289 int plugin_register_read(const char *name, int (*callback)(void));
290 /* "user_data" will be freed automatically, unless
291 * "plugin_register_complex_read" returns an error (non-zero). */
292 int plugin_register_complex_read(const char *group, const char *name,
293 plugin_read_cb callback, cdtime_t interval,
294 user_data_t const *user_data);
295 int plugin_register_write(const char *name, plugin_write_cb callback,
296 user_data_t const *user_data);
297 int plugin_register_flush(const char *name, plugin_flush_cb callback,
298 user_data_t const *user_data);
299 int plugin_register_missing(const char *name, plugin_missing_cb callback,
300 user_data_t const *user_data);
301 int plugin_register_shutdown(const char *name, plugin_shutdown_cb callback);
302 int plugin_register_data_set(const data_set_t *ds);
303 int plugin_register_log(const char *name, plugin_log_cb callback,
304 user_data_t const *user_data);
305 int plugin_register_notification(const char *name,
306 plugin_notification_cb callback,
307 user_data_t const *user_data);
309 int plugin_unregister_config(const char *name);
310 int plugin_unregister_complex_config(const char *name);
311 int plugin_unregister_init(const char *name);
312 int plugin_unregister_read(const char *name);
313 int plugin_unregister_read_group(const char *group);
314 int plugin_unregister_write(const char *name);
315 int plugin_unregister_flush(const char *name);
316 int plugin_unregister_missing(const char *name);
317 int plugin_unregister_shutdown(const char *name);
318 int plugin_unregister_data_set(const char *name);
319 int plugin_unregister_log(const char *name);
320 int plugin_unregister_notification(const char *name);
322 /*
323 * NAME
324 * plugin_log_available_writers
325 *
326 * DESCRIPTION
327 * This function can be called to output a list of _all_ registered
328 * writers to the logfacility.
329 * Since some writers dynamically build their name it can be hard for
330 * the configuring person to know it. This function will fill this gap.
331 */
332 void plugin_log_available_writers(void);
334 /*
335 * NAME
336 * plugin_dispatch_values
337 *
338 * DESCRIPTION
339 * This function is called by reading processes with the values they've
340 * aquired. The function fetches the data-set definition (that has been
341 * registered using `plugin_register_data_set') and calls _all_ registered
342 * write-functions.
343 *
344 * ARGUMENTS
345 * `vl' Value list of the values that have been read by a `read'
346 * function.
347 */
348 int plugin_dispatch_values(value_list_t const *vl);
350 /*
351 * NAME
352 * plugin_dispatch_multivalue
353 *
354 * SYNOPSIS
355 * plugin_dispatch_multivalue (vl, 1, DS_TYPE_GAUGE,
356 * "free", 42.0,
357 * "used", 58.0,
358 * NULL);
359 *
360 * DESCRIPTION
361 * Takes a list of type instances and values and dispatches that in a batch,
362 * making sure that all values have the same time stamp. If "store_percentage"
363 * is set to true, the "type" is set to "percent" and a percentage is
364 * calculated and dispatched, rather than the absolute values. Values that are
365 * NaN are dispatched as NaN and will not influence the total.
366 *
367 * The variadic arguments is a list of type_instance / type pairs, that are
368 * interpreted as type "char const *" and type, encoded by their corresponding
369 * "store_type":
370 *
371 * - "gauge_t" when "DS_TYPE_GAUGE"
372 * - "absolute_t" when "DS_TYPE_ABSOLUTE"
373 * - "derive_t" when "DS_TYPE_DERIVE"
374 * - "counter_t" when "DS_TYPE_COUNTER"
375 *
376 * The last argument must be
377 * a NULL pointer to signal end-of-list.
378 *
379 * RETURNS
380 * The number of values it failed to dispatch (zero on success).
381 */
382 __attribute__((sentinel)) int plugin_dispatch_multivalue(value_list_t const *vl,
383 _Bool store_percentage,
384 int store_type, ...);
386 int plugin_dispatch_missing(const value_list_t *vl);
388 int plugin_dispatch_notification(const notification_t *notif);
390 void plugin_log(int level, const char *format, ...)
391 __attribute__((format(printf, 2, 3)));
393 /* These functions return the parsed severity or less than zero on failure. */
394 int parse_log_severity(const char *severity);
395 int parse_notif_severity(const char *severity);
397 #define ERROR(...) plugin_log(LOG_ERR, __VA_ARGS__)
398 #define WARNING(...) plugin_log(LOG_WARNING, __VA_ARGS__)
399 #define NOTICE(...) plugin_log(LOG_NOTICE, __VA_ARGS__)
400 #define INFO(...) plugin_log(LOG_INFO, __VA_ARGS__)
401 #if COLLECT_DEBUG
402 #define DEBUG(...) plugin_log(LOG_DEBUG, __VA_ARGS__)
403 #else /* COLLECT_DEBUG */
404 #define DEBUG(...) /* noop */
405 #endif /* ! COLLECT_DEBUG */
407 const data_set_t *plugin_get_ds(const char *name);
409 int plugin_notification_meta_add_string(notification_t *n, const char *name,
410 const char *value);
411 int plugin_notification_meta_add_signed_int(notification_t *n, const char *name,
412 int64_t value);
413 int plugin_notification_meta_add_unsigned_int(notification_t *n,
414 const char *name, uint64_t value);
415 int plugin_notification_meta_add_double(notification_t *n, const char *name,
416 double value);
417 int plugin_notification_meta_add_boolean(notification_t *n, const char *name,
418 _Bool value);
420 int plugin_notification_meta_copy(notification_t *dst,
421 const notification_t *src);
423 int plugin_notification_meta_free(notification_meta_t *n);
425 /*
426 * Plugin context management.
427 */
429 void plugin_init_ctx(void);
431 plugin_ctx_t plugin_get_ctx(void);
432 plugin_ctx_t plugin_set_ctx(plugin_ctx_t ctx);
434 /*
435 * NAME
436 * plugin_get_interval
437 *
438 * DESCRIPTION
439 * This function returns the current value of the plugin's interval. The
440 * return value will be strictly greater than zero in all cases. If
441 * everything else fails, it will fall back to 10 seconds.
442 */
443 cdtime_t plugin_get_interval(void);
445 /*
446 * Context-aware thread management.
447 */
449 int plugin_thread_create(pthread_t *thread, const pthread_attr_t *attr,
450 void *(*start_routine)(void *), void *arg,
451 char const *name);
453 /*
454 * Plugins need to implement this
455 */
457 void module_register(void);
459 #endif /* PLUGIN_H */