1 /**
2 * collectd - src/meta_data.c
3 * Copyright (C) 2008-2011 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 **/
27 #include "collectd.h"
28 #include "plugin.h"
29 #include "meta_data.h"
31 #include <pthread.h>
33 /*
34 * Data types
35 */
36 union meta_value_u
37 {
38 char *mv_string;
39 int64_t mv_signed_int;
40 uint64_t mv_unsigned_int;
41 double mv_double;
42 _Bool mv_boolean;
43 };
44 typedef union meta_value_u meta_value_t;
46 struct meta_entry_s;
47 typedef struct meta_entry_s meta_entry_t;
48 struct meta_entry_s
49 {
50 char *key;
51 meta_value_t value;
52 int type;
53 meta_entry_t *next;
54 };
56 struct meta_data_s
57 {
58 meta_entry_t *head;
59 pthread_mutex_t lock;
60 };
62 /*
63 * Private functions
64 */
65 static char *md_strdup (const char *orig) /* {{{ */
66 {
67 size_t sz;
68 char *dest;
70 if (orig == NULL)
71 return (NULL);
73 sz = strlen (orig) + 1;
74 dest = (char *) malloc (sz);
75 if (dest == NULL)
76 return (NULL);
78 memcpy (dest, orig, sz);
80 return (dest);
81 } /* }}} char *md_strdup */
83 static meta_entry_t *md_entry_alloc (const char *key) /* {{{ */
84 {
85 meta_entry_t *e;
87 e = (meta_entry_t *) malloc (sizeof (*e));
88 if (e == NULL)
89 {
90 ERROR ("md_entry_alloc: malloc failed.");
91 return (NULL);
92 }
93 memset (e, 0, sizeof (*e));
95 e->key = md_strdup (key);
96 if (e->key == NULL)
97 {
98 free (e);
99 ERROR ("md_entry_alloc: md_strdup failed.");
100 return (NULL);
101 }
103 e->type = 0;
104 e->next = NULL;
106 return (e);
107 } /* }}} meta_entry_t *md_entry_alloc */
109 static meta_entry_t *md_entry_clone (const meta_entry_t *orig) /* {{{ */
110 {
111 meta_entry_t *copy;
113 if (orig == NULL)
114 return (NULL);
116 copy = md_entry_alloc (orig->key);
117 if (copy == NULL)
118 return (NULL);
119 copy->type = orig->type;
120 if (copy->type == MD_TYPE_STRING)
121 copy->value.mv_string = strdup (orig->value.mv_string);
122 else
123 copy->value = orig->value;
125 copy->next = md_entry_clone (orig->next);
126 return (copy);
127 } /* }}} meta_entry_t *md_entry_clone */
129 static void md_entry_free (meta_entry_t *e) /* {{{ */
130 {
131 if (e == NULL)
132 return;
134 free (e->key);
136 if (e->type == MD_TYPE_STRING)
137 free (e->value.mv_string);
139 if (e->next != NULL)
140 md_entry_free (e->next);
142 free (e);
143 } /* }}} void md_entry_free */
145 static int md_entry_insert (meta_data_t *md, meta_entry_t *e) /* {{{ */
146 {
147 meta_entry_t *this;
148 meta_entry_t *prev;
150 if ((md == NULL) || (e == NULL))
151 return (-EINVAL);
153 pthread_mutex_lock (&md->lock);
155 prev = NULL;
156 this = md->head;
157 while (this != NULL)
158 {
159 if (strcasecmp (e->key, this->key) == 0)
160 break;
162 prev = this;
163 this = this->next;
164 }
166 if (this == NULL)
167 {
168 /* This key does not exist yet. */
169 if (md->head == NULL)
170 md->head = e;
171 else
172 {
173 assert (prev != NULL);
174 prev->next = e;
175 }
177 e->next = NULL;
178 }
179 else /* (this != NULL) */
180 {
181 if (prev == NULL)
182 md->head = e;
183 else
184 prev->next = e;
186 e->next = this->next;
187 }
189 pthread_mutex_unlock (&md->lock);
191 if (this != NULL)
192 {
193 this->next = NULL;
194 md_entry_free (this);
195 }
197 return (0);
198 } /* }}} int md_entry_insert */
200 /* XXX: The lock on md must be held while calling this function! */
201 static meta_entry_t *md_entry_lookup (meta_data_t *md, /* {{{ */
202 const char *key)
203 {
204 meta_entry_t *e;
206 if ((md == NULL) || (key == NULL))
207 return (NULL);
209 for (e = md->head; e != NULL; e = e->next)
210 if (strcasecmp (key, e->key) == 0)
211 break;
213 return (e);
214 } /* }}} meta_entry_t *md_entry_lookup */
216 /*
217 * Each value_list_t*, as it is going through the system, is handled by exactly
218 * one thread. Plugins which pass a value_list_t* to another thread, e.g. the
219 * rrdtool plugin, must create a copy first. The meta data within a
220 * value_list_t* is not thread safe and doesn't need to be.
221 *
222 * The meta data associated with cache entries are a different story. There, we
223 * need to ensure exclusive locking to prevent leaks and other funky business.
224 * This is ensured by the uc_meta_data_get_*() functions.
225 */
227 /*
228 * Public functions
229 */
230 meta_data_t *meta_data_create (void) /* {{{ */
231 {
232 meta_data_t *md;
234 md = (meta_data_t *) malloc (sizeof (*md));
235 if (md == NULL)
236 {
237 ERROR ("meta_data_create: malloc failed.");
238 return (NULL);
239 }
240 memset (md, 0, sizeof (*md));
242 md->head = NULL;
243 pthread_mutex_init (&md->lock, /* attr = */ NULL);
245 return (md);
246 } /* }}} meta_data_t *meta_data_create */
248 meta_data_t *meta_data_clone (meta_data_t *orig) /* {{{ */
249 {
250 meta_data_t *copy;
252 if (orig == NULL)
253 return (NULL);
255 copy = meta_data_create ();
256 if (copy == NULL)
257 return (NULL);
259 pthread_mutex_lock (&orig->lock);
260 copy->head = md_entry_clone (orig->head);
261 pthread_mutex_unlock (&orig->lock);
263 return (copy);
264 } /* }}} meta_data_t *meta_data_clone */
266 void meta_data_destroy (meta_data_t *md) /* {{{ */
267 {
268 if (md == NULL)
269 return;
271 md_entry_free (md->head);
272 pthread_mutex_destroy (&md->lock);
273 free (md);
274 } /* }}} void meta_data_destroy */
276 int meta_data_exists (meta_data_t *md, const char *key) /* {{{ */
277 {
278 meta_entry_t *e;
280 if ((md == NULL) || (key == NULL))
281 return (-EINVAL);
283 pthread_mutex_lock (&md->lock);
285 for (e = md->head; e != NULL; e = e->next)
286 {
287 if (strcasecmp (key, e->key) == 0)
288 {
289 pthread_mutex_unlock (&md->lock);
290 return (1);
291 }
292 }
294 pthread_mutex_unlock (&md->lock);
295 return (0);
296 } /* }}} int meta_data_exists */
298 int meta_data_type (meta_data_t *md, const char *key) /* {{{ */
299 {
300 meta_entry_t *e;
302 if ((md == NULL) || (key == NULL))
303 return -EINVAL;
305 pthread_mutex_lock (&md->lock);
307 for (e = md->head; e != NULL; e = e->next)
308 {
309 if (strcasecmp (key, e->key) == 0)
310 {
311 pthread_mutex_unlock (&md->lock);
312 return e->type;
313 }
314 }
316 pthread_mutex_unlock (&md->lock);
317 return 0;
318 } /* }}} int meta_data_type */
320 int meta_data_toc (meta_data_t *md, char ***toc) /* {{{ */
321 {
322 int i = 0, count = 0;
323 meta_entry_t *e;
325 if ((md == NULL) || (toc == NULL))
326 return -EINVAL;
328 pthread_mutex_lock (&md->lock);
330 for (e = md->head; e != NULL; e = e->next)
331 ++count;
333 if (count == 0)
334 {
335 pthread_mutex_unlock (&md->lock);
336 return (count);
337 }
339 *toc = calloc(count, sizeof(**toc));
340 for (e = md->head; e != NULL; e = e->next)
341 (*toc)[i++] = strdup(e->key);
343 pthread_mutex_unlock (&md->lock);
344 return count;
345 } /* }}} int meta_data_toc */
347 int meta_data_delete (meta_data_t *md, const char *key) /* {{{ */
348 {
349 meta_entry_t *this;
350 meta_entry_t *prev;
352 if ((md == NULL) || (key == NULL))
353 return (-EINVAL);
355 pthread_mutex_lock (&md->lock);
357 prev = NULL;
358 this = md->head;
359 while (this != NULL)
360 {
361 if (strcasecmp (key, this->key) == 0)
362 break;
364 prev = this;
365 this = this->next;
366 }
368 if (this == NULL)
369 {
370 pthread_mutex_unlock (&md->lock);
371 return (-ENOENT);
372 }
374 if (prev == NULL)
375 md->head = this->next;
376 else
377 prev->next = this->next;
379 pthread_mutex_unlock (&md->lock);
381 this->next = NULL;
382 md_entry_free (this);
384 return (0);
385 } /* }}} int meta_data_delete */
387 /*
388 * Add functions
389 */
390 int meta_data_add_string (meta_data_t *md, /* {{{ */
391 const char *key, const char *value)
392 {
393 meta_entry_t *e;
395 if ((md == NULL) || (key == NULL) || (value == NULL))
396 return (-EINVAL);
398 e = md_entry_alloc (key);
399 if (e == NULL)
400 return (-ENOMEM);
402 e->value.mv_string = md_strdup (value);
403 if (e->value.mv_string == NULL)
404 {
405 ERROR ("meta_data_add_string: md_strdup failed.");
406 md_entry_free (e);
407 return (-ENOMEM);
408 }
409 e->type = MD_TYPE_STRING;
411 return (md_entry_insert (md, e));
412 } /* }}} int meta_data_add_string */
414 int meta_data_add_signed_int (meta_data_t *md, /* {{{ */
415 const char *key, int64_t value)
416 {
417 meta_entry_t *e;
419 if ((md == NULL) || (key == NULL))
420 return (-EINVAL);
422 e = md_entry_alloc (key);
423 if (e == NULL)
424 return (-ENOMEM);
426 e->value.mv_signed_int = value;
427 e->type = MD_TYPE_SIGNED_INT;
429 return (md_entry_insert (md, e));
430 } /* }}} int meta_data_add_signed_int */
432 int meta_data_add_unsigned_int (meta_data_t *md, /* {{{ */
433 const char *key, uint64_t value)
434 {
435 meta_entry_t *e;
437 if ((md == NULL) || (key == NULL))
438 return (-EINVAL);
440 e = md_entry_alloc (key);
441 if (e == NULL)
442 return (-ENOMEM);
444 e->value.mv_unsigned_int = value;
445 e->type = MD_TYPE_UNSIGNED_INT;
447 return (md_entry_insert (md, e));
448 } /* }}} int meta_data_add_unsigned_int */
450 int meta_data_add_double (meta_data_t *md, /* {{{ */
451 const char *key, double value)
452 {
453 meta_entry_t *e;
455 if ((md == NULL) || (key == NULL))
456 return (-EINVAL);
458 e = md_entry_alloc (key);
459 if (e == NULL)
460 return (-ENOMEM);
462 e->value.mv_double = value;
463 e->type = MD_TYPE_DOUBLE;
465 return (md_entry_insert (md, e));
466 } /* }}} int meta_data_add_double */
468 int meta_data_add_boolean (meta_data_t *md, /* {{{ */
469 const char *key, _Bool value)
470 {
471 meta_entry_t *e;
473 if ((md == NULL) || (key == NULL))
474 return (-EINVAL);
476 e = md_entry_alloc (key);
477 if (e == NULL)
478 return (-ENOMEM);
480 e->value.mv_boolean = value;
481 e->type = MD_TYPE_BOOLEAN;
483 return (md_entry_insert (md, e));
484 } /* }}} int meta_data_add_boolean */
486 /*
487 * Get functions
488 */
489 int meta_data_get_string (meta_data_t *md, /* {{{ */
490 const char *key, char **value)
491 {
492 meta_entry_t *e;
493 char *temp;
495 if ((md == NULL) || (key == NULL) || (value == NULL))
496 return (-EINVAL);
498 pthread_mutex_lock (&md->lock);
500 e = md_entry_lookup (md, key);
501 if (e == NULL)
502 {
503 pthread_mutex_unlock (&md->lock);
504 return (-ENOENT);
505 }
507 if (e->type != MD_TYPE_STRING)
508 {
509 ERROR ("meta_data_get_string: Type mismatch for key `%s'", e->key);
510 pthread_mutex_unlock (&md->lock);
511 return (-ENOENT);
512 }
514 temp = md_strdup (e->value.mv_string);
515 if (temp == NULL)
516 {
517 pthread_mutex_unlock (&md->lock);
518 ERROR ("meta_data_get_string: md_strdup failed.");
519 return (-ENOMEM);
520 }
522 pthread_mutex_unlock (&md->lock);
524 *value = temp;
526 return (0);
527 } /* }}} int meta_data_get_string */
529 int meta_data_get_signed_int (meta_data_t *md, /* {{{ */
530 const char *key, int64_t *value)
531 {
532 meta_entry_t *e;
534 if ((md == NULL) || (key == NULL) || (value == NULL))
535 return (-EINVAL);
537 pthread_mutex_lock (&md->lock);
539 e = md_entry_lookup (md, key);
540 if (e == NULL)
541 {
542 pthread_mutex_unlock (&md->lock);
543 return (-ENOENT);
544 }
546 if (e->type != MD_TYPE_SIGNED_INT)
547 {
548 ERROR ("meta_data_get_signed_int: Type mismatch for key `%s'", e->key);
549 pthread_mutex_unlock (&md->lock);
550 return (-ENOENT);
551 }
553 *value = e->value.mv_signed_int;
555 pthread_mutex_unlock (&md->lock);
556 return (0);
557 } /* }}} int meta_data_get_signed_int */
559 int meta_data_get_unsigned_int (meta_data_t *md, /* {{{ */
560 const char *key, uint64_t *value)
561 {
562 meta_entry_t *e;
564 if ((md == NULL) || (key == NULL) || (value == NULL))
565 return (-EINVAL);
567 pthread_mutex_lock (&md->lock);
569 e = md_entry_lookup (md, key);
570 if (e == NULL)
571 {
572 pthread_mutex_unlock (&md->lock);
573 return (-ENOENT);
574 }
576 if (e->type != MD_TYPE_UNSIGNED_INT)
577 {
578 ERROR ("meta_data_get_unsigned_int: Type mismatch for key `%s'", e->key);
579 pthread_mutex_unlock (&md->lock);
580 return (-ENOENT);
581 }
583 *value = e->value.mv_unsigned_int;
585 pthread_mutex_unlock (&md->lock);
586 return (0);
587 } /* }}} int meta_data_get_unsigned_int */
589 int meta_data_get_double (meta_data_t *md, /* {{{ */
590 const char *key, double *value)
591 {
592 meta_entry_t *e;
594 if ((md == NULL) || (key == NULL) || (value == NULL))
595 return (-EINVAL);
597 pthread_mutex_lock (&md->lock);
599 e = md_entry_lookup (md, key);
600 if (e == NULL)
601 {
602 pthread_mutex_unlock (&md->lock);
603 return (-ENOENT);
604 }
606 if (e->type != MD_TYPE_DOUBLE)
607 {
608 ERROR ("meta_data_get_double: Type mismatch for key `%s'", e->key);
609 pthread_mutex_unlock (&md->lock);
610 return (-ENOENT);
611 }
613 *value = e->value.mv_double;
615 pthread_mutex_unlock (&md->lock);
616 return (0);
617 } /* }}} int meta_data_get_double */
619 int meta_data_get_boolean (meta_data_t *md, /* {{{ */
620 const char *key, _Bool *value)
621 {
622 meta_entry_t *e;
624 if ((md == NULL) || (key == NULL) || (value == NULL))
625 return (-EINVAL);
627 pthread_mutex_lock (&md->lock);
629 e = md_entry_lookup (md, key);
630 if (e == NULL)
631 {
632 pthread_mutex_unlock (&md->lock);
633 return (-ENOENT);
634 }
636 if (e->type != MD_TYPE_BOOLEAN)
637 {
638 ERROR ("meta_data_get_boolean: Type mismatch for key `%s'", e->key);
639 pthread_mutex_unlock (&md->lock);
640 return (-ENOENT);
641 }
643 *value = e->value.mv_boolean;
645 pthread_mutex_unlock (&md->lock);
646 return (0);
647 } /* }}} int meta_data_get_boolean */
649 /* vim: set sw=2 sts=2 et fdm=marker : */