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"
29 #include "common.h"
30 #include "plugin.h"
31 #include "meta_data.h"
33 #define MD_MAX_NONSTRING_CHARS 128
35 /*
36 * Data types
37 */
38 union meta_value_u
39 {
40 char *mv_string;
41 int64_t mv_signed_int;
42 uint64_t mv_unsigned_int;
43 double mv_double;
44 _Bool mv_boolean;
45 };
46 typedef union meta_value_u meta_value_t;
48 struct meta_entry_s;
49 typedef struct meta_entry_s meta_entry_t;
50 struct meta_entry_s
51 {
52 char *key;
53 meta_value_t value;
54 int type;
55 meta_entry_t *next;
56 };
58 struct meta_data_s
59 {
60 meta_entry_t *head;
61 pthread_mutex_t lock;
62 };
64 /*
65 * Private functions
66 */
67 static char *md_strdup (const char *orig) /* {{{ */
68 {
69 size_t sz;
70 char *dest;
72 if (orig == NULL)
73 return (NULL);
75 sz = strlen (orig) + 1;
76 dest = malloc (sz);
77 if (dest == NULL)
78 return (NULL);
80 memcpy (dest, orig, sz);
82 return (dest);
83 } /* }}} char *md_strdup */
85 static meta_entry_t *md_entry_alloc (const char *key) /* {{{ */
86 {
87 meta_entry_t *e;
89 e = calloc (1, sizeof (*e));
90 if (e == NULL)
91 {
92 ERROR ("md_entry_alloc: calloc failed.");
93 return (NULL);
94 }
96 e->key = md_strdup (key);
97 if (e->key == NULL)
98 {
99 free (e);
100 ERROR ("md_entry_alloc: md_strdup failed.");
101 return (NULL);
102 }
104 e->type = 0;
105 e->next = NULL;
107 return (e);
108 } /* }}} meta_entry_t *md_entry_alloc */
110 /* XXX: The lock on md must be held while calling this function! */
111 static meta_entry_t *md_entry_clone_contents (const meta_entry_t *orig) /* {{{ */
112 {
113 meta_entry_t *copy;
115 /* WARNINGS :
116 * - we do not check that orig != NULL here. You should have done it before.
117 * - we do not set copy->next. DO NOT FORGET TO SET copy->next IN YOUR FUNCTION
118 */
120 copy = md_entry_alloc (orig->key);
121 if (copy == NULL)
122 return (NULL);
123 copy->type = orig->type;
124 if (copy->type == MD_TYPE_STRING)
125 copy->value.mv_string = strdup (orig->value.mv_string);
126 else
127 copy->value = orig->value;
129 return (copy);
130 } /* }}} meta_entry_t *md_entry_clone_contents */
132 static meta_entry_t *md_entry_clone (const meta_entry_t *orig) /* {{{ */
133 {
134 meta_entry_t *copy;
136 if (orig == NULL)
137 return (NULL);
139 copy = md_entry_clone_contents(orig);
141 copy->next = md_entry_clone (orig->next);
142 return (copy);
143 } /* }}} meta_entry_t *md_entry_clone */
145 static void md_entry_free (meta_entry_t *e) /* {{{ */
146 {
147 if (e == NULL)
148 return;
150 free (e->key);
152 if (e->type == MD_TYPE_STRING)
153 free (e->value.mv_string);
155 if (e->next != NULL)
156 md_entry_free (e->next);
158 free (e);
159 } /* }}} void md_entry_free */
161 static int md_entry_insert (meta_data_t *md, meta_entry_t *e) /* {{{ */
162 {
163 meta_entry_t *this;
164 meta_entry_t *prev;
166 if ((md == NULL) || (e == NULL))
167 return (-EINVAL);
169 pthread_mutex_lock (&md->lock);
171 prev = NULL;
172 this = md->head;
173 while (this != NULL)
174 {
175 if (strcasecmp (e->key, this->key) == 0)
176 break;
178 prev = this;
179 this = this->next;
180 }
182 if (this == NULL)
183 {
184 /* This key does not exist yet. */
185 if (md->head == NULL)
186 md->head = e;
187 else
188 {
189 assert (prev != NULL);
190 prev->next = e;
191 }
193 e->next = NULL;
194 }
195 else /* (this != NULL) */
196 {
197 if (prev == NULL)
198 md->head = e;
199 else
200 prev->next = e;
202 e->next = this->next;
203 }
205 pthread_mutex_unlock (&md->lock);
207 if (this != NULL)
208 {
209 this->next = NULL;
210 md_entry_free (this);
211 }
213 return (0);
214 } /* }}} int md_entry_insert */
216 /* XXX: The lock on md must be held while calling this function! */
217 static int md_entry_insert_clone (meta_data_t *md, meta_entry_t *orig) /* {{{ */
218 {
219 meta_entry_t *e;
220 meta_entry_t *this;
221 meta_entry_t *prev;
223 /* WARNINGS :
224 * - we do not check that md and e != NULL here. You should have done it before.
225 * - we do not use the lock. You should have set it before.
226 */
228 e = md_entry_clone_contents(orig);
230 prev = NULL;
231 this = md->head;
232 while (this != NULL)
233 {
234 if (strcasecmp (e->key, this->key) == 0)
235 break;
237 prev = this;
238 this = this->next;
239 }
241 if (this == NULL)
242 {
243 /* This key does not exist yet. */
244 if (md->head == NULL)
245 md->head = e;
246 else
247 {
248 assert (prev != NULL);
249 prev->next = e;
250 }
252 e->next = NULL;
253 }
254 else /* (this != NULL) */
255 {
256 if (prev == NULL)
257 md->head = e;
258 else
259 prev->next = e;
261 e->next = this->next;
262 }
264 if (this != NULL)
265 {
266 this->next = NULL;
267 md_entry_free (this);
268 }
270 return (0);
271 } /* }}} int md_entry_insert_clone */
273 /* XXX: The lock on md must be held while calling this function! */
274 static meta_entry_t *md_entry_lookup (meta_data_t *md, /* {{{ */
275 const char *key)
276 {
277 meta_entry_t *e;
279 if ((md == NULL) || (key == NULL))
280 return (NULL);
282 for (e = md->head; e != NULL; e = e->next)
283 if (strcasecmp (key, e->key) == 0)
284 break;
286 return (e);
287 } /* }}} meta_entry_t *md_entry_lookup */
289 /*
290 * Each value_list_t*, as it is going through the system, is handled by exactly
291 * one thread. Plugins which pass a value_list_t* to another thread, e.g. the
292 * rrdtool plugin, must create a copy first. The meta data within a
293 * value_list_t* is not thread safe and doesn't need to be.
294 *
295 * The meta data associated with cache entries are a different story. There, we
296 * need to ensure exclusive locking to prevent leaks and other funky business.
297 * This is ensured by the uc_meta_data_get_*() functions.
298 */
300 /*
301 * Public functions
302 */
303 meta_data_t *meta_data_create (void) /* {{{ */
304 {
305 meta_data_t *md;
307 md = calloc (1, sizeof (*md));
308 if (md == NULL)
309 {
310 ERROR ("meta_data_create: calloc failed.");
311 return (NULL);
312 }
314 pthread_mutex_init (&md->lock, /* attr = */ NULL);
316 return (md);
317 } /* }}} meta_data_t *meta_data_create */
319 meta_data_t *meta_data_clone (meta_data_t *orig) /* {{{ */
320 {
321 meta_data_t *copy;
323 if (orig == NULL)
324 return (NULL);
326 copy = meta_data_create ();
327 if (copy == NULL)
328 return (NULL);
330 pthread_mutex_lock (&orig->lock);
331 copy->head = md_entry_clone (orig->head);
332 pthread_mutex_unlock (&orig->lock);
334 return (copy);
335 } /* }}} meta_data_t *meta_data_clone */
337 int meta_data_clone_merge (meta_data_t **dest, meta_data_t *orig) /* {{{ */
338 {
339 if (orig == NULL)
340 return (0);
342 if (*dest == NULL) {
343 *dest = meta_data_clone(orig);
344 return(0);
345 }
347 pthread_mutex_lock (&orig->lock);
348 for (meta_entry_t *e=orig->head; e != NULL; e = e->next)
349 {
350 md_entry_insert_clone((*dest), e);
351 }
352 pthread_mutex_unlock (&orig->lock);
354 return (0);
355 } /* }}} int meta_data_clone_merge */
357 void meta_data_destroy (meta_data_t *md) /* {{{ */
358 {
359 if (md == NULL)
360 return;
362 md_entry_free (md->head);
363 pthread_mutex_destroy (&md->lock);
364 free (md);
365 } /* }}} void meta_data_destroy */
367 int meta_data_exists (meta_data_t *md, const char *key) /* {{{ */
368 {
369 if ((md == NULL) || (key == NULL))
370 return (-EINVAL);
372 pthread_mutex_lock (&md->lock);
374 for (meta_entry_t *e = md->head; e != NULL; e = e->next)
375 {
376 if (strcasecmp (key, e->key) == 0)
377 {
378 pthread_mutex_unlock (&md->lock);
379 return (1);
380 }
381 }
383 pthread_mutex_unlock (&md->lock);
384 return (0);
385 } /* }}} int meta_data_exists */
387 int meta_data_type (meta_data_t *md, const char *key) /* {{{ */
388 {
389 if ((md == NULL) || (key == NULL))
390 return -EINVAL;
392 pthread_mutex_lock (&md->lock);
394 for (meta_entry_t *e = md->head; e != NULL; e = e->next)
395 {
396 if (strcasecmp (key, e->key) == 0)
397 {
398 pthread_mutex_unlock (&md->lock);
399 return e->type;
400 }
401 }
403 pthread_mutex_unlock (&md->lock);
404 return 0;
405 } /* }}} int meta_data_type */
407 int meta_data_toc (meta_data_t *md, char ***toc) /* {{{ */
408 {
409 int i = 0, count = 0;
411 if ((md == NULL) || (toc == NULL))
412 return -EINVAL;
414 pthread_mutex_lock (&md->lock);
416 for (meta_entry_t *e = md->head; e != NULL; e = e->next)
417 ++count;
419 if (count == 0)
420 {
421 pthread_mutex_unlock (&md->lock);
422 return (count);
423 }
425 *toc = calloc(count, sizeof(**toc));
426 for (meta_entry_t *e = md->head; e != NULL; e = e->next)
427 (*toc)[i++] = strdup(e->key);
429 pthread_mutex_unlock (&md->lock);
430 return count;
431 } /* }}} int meta_data_toc */
433 int meta_data_delete (meta_data_t *md, const char *key) /* {{{ */
434 {
435 meta_entry_t *this;
436 meta_entry_t *prev;
438 if ((md == NULL) || (key == NULL))
439 return (-EINVAL);
441 pthread_mutex_lock (&md->lock);
443 prev = NULL;
444 this = md->head;
445 while (this != NULL)
446 {
447 if (strcasecmp (key, this->key) == 0)
448 break;
450 prev = this;
451 this = this->next;
452 }
454 if (this == NULL)
455 {
456 pthread_mutex_unlock (&md->lock);
457 return (-ENOENT);
458 }
460 if (prev == NULL)
461 md->head = this->next;
462 else
463 prev->next = this->next;
465 pthread_mutex_unlock (&md->lock);
467 this->next = NULL;
468 md_entry_free (this);
470 return (0);
471 } /* }}} int meta_data_delete */
473 /*
474 * Add functions
475 */
476 int meta_data_add_string (meta_data_t *md, /* {{{ */
477 const char *key, const char *value)
478 {
479 meta_entry_t *e;
481 if ((md == NULL) || (key == NULL) || (value == NULL))
482 return (-EINVAL);
484 e = md_entry_alloc (key);
485 if (e == NULL)
486 return (-ENOMEM);
488 e->value.mv_string = md_strdup (value);
489 if (e->value.mv_string == NULL)
490 {
491 ERROR ("meta_data_add_string: md_strdup failed.");
492 md_entry_free (e);
493 return (-ENOMEM);
494 }
495 e->type = MD_TYPE_STRING;
497 return (md_entry_insert (md, e));
498 } /* }}} int meta_data_add_string */
500 int meta_data_add_signed_int (meta_data_t *md, /* {{{ */
501 const char *key, int64_t value)
502 {
503 meta_entry_t *e;
505 if ((md == NULL) || (key == NULL))
506 return (-EINVAL);
508 e = md_entry_alloc (key);
509 if (e == NULL)
510 return (-ENOMEM);
512 e->value.mv_signed_int = value;
513 e->type = MD_TYPE_SIGNED_INT;
515 return (md_entry_insert (md, e));
516 } /* }}} int meta_data_add_signed_int */
518 int meta_data_add_unsigned_int (meta_data_t *md, /* {{{ */
519 const char *key, uint64_t value)
520 {
521 meta_entry_t *e;
523 if ((md == NULL) || (key == NULL))
524 return (-EINVAL);
526 e = md_entry_alloc (key);
527 if (e == NULL)
528 return (-ENOMEM);
530 e->value.mv_unsigned_int = value;
531 e->type = MD_TYPE_UNSIGNED_INT;
533 return (md_entry_insert (md, e));
534 } /* }}} int meta_data_add_unsigned_int */
536 int meta_data_add_double (meta_data_t *md, /* {{{ */
537 const char *key, double value)
538 {
539 meta_entry_t *e;
541 if ((md == NULL) || (key == NULL))
542 return (-EINVAL);
544 e = md_entry_alloc (key);
545 if (e == NULL)
546 return (-ENOMEM);
548 e->value.mv_double = value;
549 e->type = MD_TYPE_DOUBLE;
551 return (md_entry_insert (md, e));
552 } /* }}} int meta_data_add_double */
554 int meta_data_add_boolean (meta_data_t *md, /* {{{ */
555 const char *key, _Bool value)
556 {
557 meta_entry_t *e;
559 if ((md == NULL) || (key == NULL))
560 return (-EINVAL);
562 e = md_entry_alloc (key);
563 if (e == NULL)
564 return (-ENOMEM);
566 e->value.mv_boolean = value;
567 e->type = MD_TYPE_BOOLEAN;
569 return (md_entry_insert (md, e));
570 } /* }}} int meta_data_add_boolean */
572 /*
573 * Get functions
574 */
575 int meta_data_get_string (meta_data_t *md, /* {{{ */
576 const char *key, char **value)
577 {
578 meta_entry_t *e;
579 char *temp;
581 if ((md == NULL) || (key == NULL) || (value == NULL))
582 return (-EINVAL);
584 pthread_mutex_lock (&md->lock);
586 e = md_entry_lookup (md, key);
587 if (e == NULL)
588 {
589 pthread_mutex_unlock (&md->lock);
590 return (-ENOENT);
591 }
593 if (e->type != MD_TYPE_STRING)
594 {
595 ERROR ("meta_data_get_string: Type mismatch for key `%s'", e->key);
596 pthread_mutex_unlock (&md->lock);
597 return (-ENOENT);
598 }
600 temp = md_strdup (e->value.mv_string);
601 if (temp == NULL)
602 {
603 pthread_mutex_unlock (&md->lock);
604 ERROR ("meta_data_get_string: md_strdup failed.");
605 return (-ENOMEM);
606 }
608 pthread_mutex_unlock (&md->lock);
610 *value = temp;
612 return (0);
613 } /* }}} int meta_data_get_string */
615 int meta_data_get_signed_int (meta_data_t *md, /* {{{ */
616 const char *key, int64_t *value)
617 {
618 meta_entry_t *e;
620 if ((md == NULL) || (key == NULL) || (value == NULL))
621 return (-EINVAL);
623 pthread_mutex_lock (&md->lock);
625 e = md_entry_lookup (md, key);
626 if (e == NULL)
627 {
628 pthread_mutex_unlock (&md->lock);
629 return (-ENOENT);
630 }
632 if (e->type != MD_TYPE_SIGNED_INT)
633 {
634 ERROR ("meta_data_get_signed_int: Type mismatch for key `%s'", e->key);
635 pthread_mutex_unlock (&md->lock);
636 return (-ENOENT);
637 }
639 *value = e->value.mv_signed_int;
641 pthread_mutex_unlock (&md->lock);
642 return (0);
643 } /* }}} int meta_data_get_signed_int */
645 int meta_data_get_unsigned_int (meta_data_t *md, /* {{{ */
646 const char *key, uint64_t *value)
647 {
648 meta_entry_t *e;
650 if ((md == NULL) || (key == NULL) || (value == NULL))
651 return (-EINVAL);
653 pthread_mutex_lock (&md->lock);
655 e = md_entry_lookup (md, key);
656 if (e == NULL)
657 {
658 pthread_mutex_unlock (&md->lock);
659 return (-ENOENT);
660 }
662 if (e->type != MD_TYPE_UNSIGNED_INT)
663 {
664 ERROR ("meta_data_get_unsigned_int: Type mismatch for key `%s'", e->key);
665 pthread_mutex_unlock (&md->lock);
666 return (-ENOENT);
667 }
669 *value = e->value.mv_unsigned_int;
671 pthread_mutex_unlock (&md->lock);
672 return (0);
673 } /* }}} int meta_data_get_unsigned_int */
675 int meta_data_get_double (meta_data_t *md, /* {{{ */
676 const char *key, double *value)
677 {
678 meta_entry_t *e;
680 if ((md == NULL) || (key == NULL) || (value == NULL))
681 return (-EINVAL);
683 pthread_mutex_lock (&md->lock);
685 e = md_entry_lookup (md, key);
686 if (e == NULL)
687 {
688 pthread_mutex_unlock (&md->lock);
689 return (-ENOENT);
690 }
692 if (e->type != MD_TYPE_DOUBLE)
693 {
694 ERROR ("meta_data_get_double: Type mismatch for key `%s'", e->key);
695 pthread_mutex_unlock (&md->lock);
696 return (-ENOENT);
697 }
699 *value = e->value.mv_double;
701 pthread_mutex_unlock (&md->lock);
702 return (0);
703 } /* }}} int meta_data_get_double */
705 int meta_data_get_boolean (meta_data_t *md, /* {{{ */
706 const char *key, _Bool *value)
707 {
708 meta_entry_t *e;
710 if ((md == NULL) || (key == NULL) || (value == NULL))
711 return (-EINVAL);
713 pthread_mutex_lock (&md->lock);
715 e = md_entry_lookup (md, key);
716 if (e == NULL)
717 {
718 pthread_mutex_unlock (&md->lock);
719 return (-ENOENT);
720 }
722 if (e->type != MD_TYPE_BOOLEAN)
723 {
724 ERROR ("meta_data_get_boolean: Type mismatch for key `%s'", e->key);
725 pthread_mutex_unlock (&md->lock);
726 return (-ENOENT);
727 }
729 *value = e->value.mv_boolean;
731 pthread_mutex_unlock (&md->lock);
732 return (0);
733 } /* }}} int meta_data_get_boolean */
735 int meta_data_as_string (meta_data_t *md, /* {{{ */
736 const char *key, char **value)
737 {
738 meta_entry_t *e;
739 char *actual;
740 char buffer[MD_MAX_NONSTRING_CHARS]; /* For non-string types. */
741 char *temp;
742 int type;
744 if ((md == NULL) || (key == NULL) || (value == NULL))
745 return (-EINVAL);
747 pthread_mutex_lock (&md->lock);
749 e = md_entry_lookup (md, key);
750 if (e == NULL)
751 {
752 pthread_mutex_unlock (&md->lock);
753 return (-ENOENT);
754 }
756 type = e->type;
758 switch (type)
759 {
760 case MD_TYPE_STRING:
761 actual = e->value.mv_string;
762 break;
763 case MD_TYPE_SIGNED_INT:
764 ssnprintf (buffer, sizeof (buffer), "%"PRIi64, e->value.mv_signed_int);
765 actual = buffer;
766 break;
767 case MD_TYPE_UNSIGNED_INT:
768 ssnprintf (buffer, sizeof (buffer), "%"PRIu64, e->value.mv_unsigned_int);
769 actual = buffer;
770 break;
771 case MD_TYPE_DOUBLE:
772 ssnprintf (buffer, sizeof (buffer), GAUGE_FORMAT, e->value.mv_double);
773 actual = buffer;
774 break;
775 case MD_TYPE_BOOLEAN:
776 actual = e->value.mv_boolean ? "true" : "false";
777 break;
778 default:
779 pthread_mutex_unlock (&md->lock);
780 ERROR ("meta_data_as_string: unknown type %d for key `%s'", type, key);
781 return (-ENOENT);
782 }
784 pthread_mutex_unlock (&md->lock);
786 temp = md_strdup (actual);
787 if (temp == NULL)
788 {
789 pthread_mutex_unlock (&md->lock);
790 ERROR ("meta_data_as_string: md_strdup failed for key `%s'.", key);
791 return (-ENOMEM);
792 }
794 *value = temp;
796 return (0);
797 } /* }}} int meta_data_as_string */
799 /* vim: set sw=2 sts=2 et fdm=marker : */