Asterisk - The Open Source Telephony Project  GIT-master-e8cda4b
astobj2_hash.c
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1 /*
2  * astobj2_hash - Hash table implementation for astobj2.
3  *
4  * Copyright (C) 2006 Marta Carbone, Luigi Rizzo - Univ. di Pisa, Italy
5  *
6  * See http://www.asterisk.org for more information about
7  * the Asterisk project. Please do not directly contact
8  * any of the maintainers of this project for assistance;
9  * the project provides a web site, mailing lists and IRC
10  * channels for your use.
11  *
12  * This program is free software, distributed under the terms of
13  * the GNU General Public License Version 2. See the LICENSE file
14  * at the top of the source tree.
15  */
16 
17 /*! \file
18  *
19  * \brief Hash table functions implementing astobj2 containers.
20  *
21  * \author Richard Mudgett <rmudgett@digium.com>
22  */
23 
24 #include "asterisk.h"
25 
26 #include "asterisk/_private.h"
27 #include "asterisk/astobj2.h"
28 #include "astobj2_private.h"
30 #include "asterisk/dlinkedlists.h"
31 #include "asterisk/utils.h"
32 
33 /*!
34  * A structure to create a linked list of entries,
35  * used within a bucket.
36  */
38  /*!
39  * \brief Items common to all container nodes.
40  * \note Must be first in the specific node struct.
41  */
43  /*! Next node links in the list. */
45  /*! Hash bucket holding the node. */
46  int my_bucket;
47 };
48 
49 struct hash_bucket {
50  /*! List of objects held in the bucket. */
52 #if defined(AO2_DEBUG)
53  /*! Number of elements currently in the bucket. */
54  int elements;
55  /*! Maximum number of elements in the bucket. */
56  int max_elements;
57 #endif /* defined(AO2_DEBUG) */
58 };
59 
60 /*!
61  * A hash container in addition to values common to all
62  * container types, stores the hash callback function, the
63  * number of hash buckets, and the hash bucket heads.
64  */
66  /*!
67  * \brief Items common to all containers.
68  * \note Must be first in the specific container struct.
69  */
72  /*! Number of hash buckets in this container. */
73  int n_buckets;
74  /*! Hash bucket array of n_buckets. Variable size. */
75  struct hash_bucket buckets[0];
76 };
77 
78 /*! Traversal state to restart a hash container traversal. */
80  /*! Active sort function in the traversal if not NULL. */
82  /*! Saved comparison callback arg pointer. */
83  void *arg;
84  /*! Starting hash bucket */
86  /*! Stopping hash bucket */
88  /*! Saved search flags to control traversing the container. */
89  enum search_flags flags;
90  /*! TRUE if it is a descending search */
91  unsigned int descending:1;
92 };
93 
95  /*
96  * If we have a division by zero compile error here then there
97  * is not enough room for the state. Increase AO2_TRAVERSAL_STATE_SIZE.
98  */
99  char check[1 / (AO2_TRAVERSAL_STATE_SIZE / sizeof(struct hash_traversal_state))];
100 };
101 
102 /*!
103  * \internal
104  * \brief Create an empty copy of this container.
105  * \since 14.0.0
106  *
107  * \param self Container to operate upon.
108  * \param tag used for debugging.
109  * \param file Debug file name invoked from
110  * \param line Debug line invoked from
111  * \param func Debug function name invoked from
112  *
113  * \retval empty-clone-container on success.
114  * \retval NULL on error.
115  */
117  const char *tag, const char *file, int line, const char *func)
118 {
119  if (!__is_ao2_object(self, file, line, func)) {
120  return NULL;
121  }
122 
123  return __ao2_container_alloc_hash(ao2_options_get(self), self->common.options,
124  self->n_buckets, self->hash_fn, self->common.sort_fn, self->common.cmp_fn,
125  tag, file, line, func);
126 }
127 
128 /*!
129  * \internal
130  * \brief Destroy a hash container list node.
131  * \since 12.0.0
132  *
133  * \param v_doomed Container node to destroy.
134  *
135  * \details
136  * The container node unlinks itself from the container as part
137  * of its destruction. The node must be destroyed while the
138  * container is already locked.
139  *
140  * \note The container must be locked when the node is
141  * unreferenced.
142  *
143  * \return Nothing
144  */
145 static void hash_ao2_node_destructor(void *v_doomed)
146 {
147  struct hash_bucket_node *doomed = v_doomed;
148 
149  if (doomed->common.is_linked) {
150  struct ao2_container_hash *my_container;
151  struct hash_bucket *bucket;
152 
153  /*
154  * Promote to write lock if not already there. Since
155  * adjust_lock() can potentially release and block waiting for a
156  * write lock, care must be taken to ensure that node references
157  * are released before releasing the container references.
158  *
159  * Node references held by an iterator can only be held while
160  * the iterator also holds a reference to the container. These
161  * node references must be unreferenced before the container can
162  * be unreferenced to ensure that the node will not get a
163  * negative reference and the destructor called twice for the
164  * same node.
165  */
166  my_container = (struct ao2_container_hash *) doomed->common.my_container;
167 #ifdef AST_DEVMODE
168  is_ao2_object(my_container);
169 #endif
170 
171  __adjust_lock(my_container, AO2_LOCK_REQ_WRLOCK, 1);
172 
173 #if defined(AO2_DEBUG)
174  if (!my_container->common.destroying
176  ast_log(LOG_ERROR, "Container integrity failed before node deletion.\n");
177  }
178 #endif /* defined(AO2_DEBUG) */
179  bucket = &my_container->buckets[doomed->my_bucket];
180  AST_DLLIST_REMOVE(&bucket->list, doomed, links);
181  AO2_DEVMODE_STAT(--my_container->common.nodes);
182  }
183 
184  /*
185  * We could have an object in the node if the container is being
186  * destroyed or the node had not been linked in yet.
187  */
188  if (doomed->common.obj) {
190  }
191 }
192 
193 /*!
194  * \internal
195  * \brief Create a new container node.
196  * \since 12.0.0
197  *
198  * \param self Container to operate upon.
199  * \param obj_new Object to put into the node.
200  * \param tag used for debugging.
201  * \param file Debug file name invoked from
202  * \param line Debug line invoked from
203  * \param func Debug function name invoked from
204  *
205  * \retval initialized-node on success.
206  * \retval NULL on error.
207  */
208 static struct hash_bucket_node *hash_ao2_new_node(struct ao2_container_hash *self, void *obj_new, const char *tag, const char *file, int line, const char *func)
209 {
210  struct hash_bucket_node *node;
211  int i;
212 
213  node = ao2_alloc_options(sizeof(*node), hash_ao2_node_destructor,
215  if (!node) {
216  return NULL;
217  }
218 
219  i = abs(self->hash_fn(obj_new, OBJ_SEARCH_OBJECT) % self->n_buckets);
220 
221  __ao2_ref(obj_new, +1, tag ?: "Container node creation", file, line, func);
222  node->common.obj = obj_new;
223  node->common.my_container = (struct ao2_container *) self;
224  node->my_bucket = i;
225 
226  return node;
227 }
228 
229 /*!
230  * \internal
231  * \brief Insert a node into this container.
232  * \since 12.0.0
233  *
234  * \param self Container to operate upon.
235  * \param node Container node to insert into the container.
236  *
237  * \return enum ao2_container_insert value.
238  */
240  struct hash_bucket_node *node)
241 {
242  int cmp;
243  struct hash_bucket *bucket;
244  struct hash_bucket_node *cur;
245  ao2_sort_fn *sort_fn;
246  uint32_t options;
247 
248  bucket = &self->buckets[node->my_bucket];
249  sort_fn = self->common.sort_fn;
250  options = self->common.options;
251 
252  if (options & AO2_CONTAINER_ALLOC_OPT_INSERT_BEGIN) {
253  if (sort_fn) {
255  cmp = sort_fn(cur->common.obj, node->common.obj, OBJ_SEARCH_OBJECT);
256  if (cmp > 0) {
257  continue;
258  }
259  if (cmp < 0) {
262  }
263  switch (options & AO2_CONTAINER_ALLOC_OPT_DUPS_MASK) {
264  default:
266  break;
268  /* Reject all objects with the same key. */
271  if (cur->common.obj == node->common.obj) {
272  /* Reject inserting the same object */
274  }
275  break;
277  SWAP(cur->common.obj, node->common.obj);
278  ao2_ref(node, -1);
280  }
281  }
283  }
284  AST_DLLIST_INSERT_HEAD(&bucket->list, node, links);
285  } else {
286  if (sort_fn) {
287  AST_DLLIST_TRAVERSE_SAFE_BEGIN(&bucket->list, cur, links) {
288  cmp = sort_fn(cur->common.obj, node->common.obj, OBJ_SEARCH_OBJECT);
289  if (cmp < 0) {
290  continue;
291  }
292  if (cmp > 0) {
295  }
296  switch (options & AO2_CONTAINER_ALLOC_OPT_DUPS_MASK) {
297  default:
299  break;
301  /* Reject all objects with the same key. */
304  if (cur->common.obj == node->common.obj) {
305  /* Reject inserting the same object */
307  }
308  break;
310  SWAP(cur->common.obj, node->common.obj);
311  ao2_ref(node, -1);
313  }
314  }
316  }
317  AST_DLLIST_INSERT_TAIL(&bucket->list, node, links);
318  }
320 }
321 
322 /*!
323  * \internal
324  * \brief Find the first hash container node in a traversal.
325  * \since 12.0.0
326  *
327  * \param self Container to operate upon.
328  * \param flags search_flags to control traversing the container
329  * \param arg Comparison callback arg parameter.
330  * \param state Traversal state to restart hash container traversal.
331  *
332  * \retval node-ptr of found node (Reffed).
333  * \retval NULL when no node found.
334  */
335 static struct hash_bucket_node *hash_ao2_find_first(struct ao2_container_hash *self, enum search_flags flags, void *arg, struct hash_traversal_state *state)
336 {
337  struct hash_bucket_node *node;
338  int bucket_cur;
339  int cmp;
340 
341  memset(state, 0, sizeof(*state));
342  state->arg = arg;
343  state->flags = flags;
344 
345  /* Determine traversal order. */
346  switch (flags & OBJ_ORDER_MASK) {
347  case OBJ_ORDER_POST:
349  state->descending = 1;
350  break;
351  case OBJ_ORDER_PRE:
352  case OBJ_ORDER_ASCENDING:
353  default:
354  break;
355  }
356 
357  /*
358  * If lookup by pointer or search key, run the hash and optional
359  * sort functions. Otherwise, traverse the whole container.
360  */
361  switch (flags & OBJ_SEARCH_MASK) {
362  case OBJ_SEARCH_OBJECT:
363  case OBJ_SEARCH_KEY:
364  /* we know hash can handle this case */
365  bucket_cur = abs(self->hash_fn(arg, flags & OBJ_SEARCH_MASK)
366  % self->n_buckets);
367  state->sort_fn = self->common.sort_fn;
368  break;
370  /* scan all buckets for partial key matches */
371  bucket_cur = -1;
372  state->sort_fn = self->common.sort_fn;
373  break;
374  default:
375  /* don't know, let's scan all buckets */
376  bucket_cur = -1;
377  state->sort_fn = NULL;
378  break;
379  }
380 
381  if (state->descending) {
382  /*
383  * Determine the search boundaries of a descending traversal.
384  *
385  * bucket_cur downto state->bucket_last
386  */
387  if (bucket_cur < 0) {
388  bucket_cur = self->n_buckets - 1;
389  state->bucket_last = 0;
390  } else {
391  state->bucket_last = bucket_cur;
392  }
393  state->bucket_start = bucket_cur;
394 
395  /* For each bucket */
396  for (; state->bucket_last <= bucket_cur; --bucket_cur) {
397  /* For each node in the bucket. */
398  for (node = AST_DLLIST_LAST(&self->buckets[bucket_cur].list);
399  node;
400  node = AST_DLLIST_PREV(node, links)) {
401  if (!node->common.obj) {
402  /* Node is empty */
403  continue;
404  }
405 
406  if (state->sort_fn) {
407  /* Filter node through the sort_fn */
408  cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK);
409  if (cmp > 0) {
410  continue;
411  }
412  if (cmp < 0) {
413  /* No more nodes in this bucket are possible to match. */
414  break;
415  }
416  }
417 
418  /* We have the first traversal node */
419  ao2_ref(node, +1);
420  return node;
421  }
422  }
423  } else {
424  /*
425  * Determine the search boundaries of an ascending traversal.
426  *
427  * bucket_cur to state->bucket_last-1
428  */
429  if (bucket_cur < 0) {
430  bucket_cur = 0;
431  state->bucket_last = self->n_buckets;
432  } else {
433  state->bucket_last = bucket_cur + 1;
434  }
435  state->bucket_start = bucket_cur;
436 
437  /* For each bucket */
438  for (; bucket_cur < state->bucket_last; ++bucket_cur) {
439  /* For each node in the bucket. */
440  for (node = AST_DLLIST_FIRST(&self->buckets[bucket_cur].list);
441  node;
442  node = AST_DLLIST_NEXT(node, links)) {
443  if (!node->common.obj) {
444  /* Node is empty */
445  continue;
446  }
447 
448  if (state->sort_fn) {
449  /* Filter node through the sort_fn */
450  cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK);
451  if (cmp < 0) {
452  continue;
453  }
454  if (cmp > 0) {
455  /* No more nodes in this bucket are possible to match. */
456  break;
457  }
458  }
459 
460  /* We have the first traversal node */
461  ao2_ref(node, +1);
462  return node;
463  }
464  }
465  }
466 
467  return NULL;
468 }
469 
470 /*!
471  * \internal
472  * \brief Find the next hash container node in a traversal.
473  * \since 12.0.0
474  *
475  * \param self Container to operate upon.
476  * \param state Traversal state to restart hash container traversal.
477  * \param prev Previous node returned by the traversal search functions.
478  * The ref ownership is passed back to this function.
479  *
480  * \retval node-ptr of found node (Reffed).
481  * \retval NULL when no node found.
482  */
484 {
485  struct hash_bucket_node *node;
486  void *arg;
487  enum search_flags flags;
488  int bucket_cur;
489  int cmp;
490 
491  arg = state->arg;
492  flags = state->flags;
493  bucket_cur = prev->my_bucket;
494  node = prev;
495 
496  /*
497  * This function is structured the same as hash_ao2_find_first()
498  * intentionally. We are resuming the search loops from
499  * hash_ao2_find_first() in order to find the next node. The
500  * search loops must be resumed where hash_ao2_find_first()
501  * returned with the first node.
502  */
503  if (state->descending) {
504  goto hash_descending_resume;
505 
506  /* For each bucket */
507  for (; state->bucket_last <= bucket_cur; --bucket_cur) {
508  /* For each node in the bucket. */
509  for (node = AST_DLLIST_LAST(&self->buckets[bucket_cur].list);
510  node;
511  node = AST_DLLIST_PREV(node, links)) {
512  if (!node->common.obj) {
513  /* Node is empty */
514  continue;
515  }
516 
517  if (state->sort_fn) {
518  /* Filter node through the sort_fn */
519  cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK);
520  if (cmp > 0) {
521  continue;
522  }
523  if (cmp < 0) {
524  /* No more nodes in this bucket are possible to match. */
525  break;
526  }
527  }
528 
529  /* We have the next traversal node */
530  ao2_ref(node, +1);
531 
532  /*
533  * Dereferencing the prev node may result in our next node
534  * object being removed by another thread. This could happen if
535  * the container uses RW locks and the container was read
536  * locked.
537  */
538  ao2_ref(prev, -1);
539  if (node->common.obj) {
540  return node;
541  }
542  prev = node;
543 
544 hash_descending_resume:;
545  }
546  }
547  } else {
548  goto hash_ascending_resume;
549 
550  /* For each bucket */
551  for (; bucket_cur < state->bucket_last; ++bucket_cur) {
552  /* For each node in the bucket. */
553  for (node = AST_DLLIST_FIRST(&self->buckets[bucket_cur].list);
554  node;
555  node = AST_DLLIST_NEXT(node, links)) {
556  if (!node->common.obj) {
557  /* Node is empty */
558  continue;
559  }
560 
561  if (state->sort_fn) {
562  /* Filter node through the sort_fn */
563  cmp = state->sort_fn(node->common.obj, arg, flags & OBJ_SEARCH_MASK);
564  if (cmp < 0) {
565  continue;
566  }
567  if (cmp > 0) {
568  /* No more nodes in this bucket are possible to match. */
569  break;
570  }
571  }
572 
573  /* We have the next traversal node */
574  ao2_ref(node, +1);
575 
576  /*
577  * Dereferencing the prev node may result in our next node
578  * object being removed by another thread. This could happen if
579  * the container uses RW locks and the container was read
580  * locked.
581  */
582  ao2_ref(prev, -1);
583  if (node->common.obj) {
584  return node;
585  }
586  prev = node;
587 
588 hash_ascending_resume:;
589  }
590  }
591  }
592 
593  /* No more nodes in the container left to traverse. */
594  ao2_ref(prev, -1);
595  return NULL;
596 }
597 
598 /*!
599  * \internal
600  * \brief Find the next non-empty iteration node in the container.
601  * \since 12.0.0
602  *
603  * \param self Container to operate upon.
604  * \param node Previous node returned by the iterator.
605  * \param flags search_flags to control iterating the container.
606  * Only AO2_ITERATOR_DESCENDING is useful by the method.
607  *
608  * \note The container is already locked.
609  *
610  * \retval node on success.
611  * \retval NULL on error or no more nodes in the container.
612  */
614 {
615  int cur_bucket;
616 
617  if (flags & AO2_ITERATOR_DESCENDING) {
618  if (node) {
619  cur_bucket = node->my_bucket;
620 
621  /* Find next non-empty node. */
622  for (;;) {
623  node = AST_DLLIST_PREV(node, links);
624  if (!node) {
625  break;
626  }
627  if (node->common.obj) {
628  /* Found a non-empty node. */
629  return node;
630  }
631  }
632  } else {
633  /* Find first non-empty node. */
634  cur_bucket = self->n_buckets;
635  }
636 
637  /* Find a non-empty node in the remaining buckets */
638  while (0 <= --cur_bucket) {
639  node = AST_DLLIST_LAST(&self->buckets[cur_bucket].list);
640  while (node) {
641  if (node->common.obj) {
642  /* Found a non-empty node. */
643  return node;
644  }
645  node = AST_DLLIST_PREV(node, links);
646  }
647  }
648  } else {
649  if (node) {
650  cur_bucket = node->my_bucket;
651 
652  /* Find next non-empty node. */
653  for (;;) {
654  node = AST_DLLIST_NEXT(node, links);
655  if (!node) {
656  break;
657  }
658  if (node->common.obj) {
659  /* Found a non-empty node. */
660  return node;
661  }
662  }
663  } else {
664  /* Find first non-empty node. */
665  cur_bucket = -1;
666  }
667 
668  /* Find a non-empty node in the remaining buckets */
669  while (++cur_bucket < self->n_buckets) {
670  node = AST_DLLIST_FIRST(&self->buckets[cur_bucket].list);
671  while (node) {
672  if (node->common.obj) {
673  /* Found a non-empty node. */
674  return node;
675  }
676  node = AST_DLLIST_NEXT(node, links);
677  }
678  }
679  }
680 
681  /* No more nodes to visit in the container. */
682  return NULL;
683 }
684 
685 #if defined(AO2_DEBUG)
686 /*!
687  * \internal
688  * \brief Increment the hash container linked object statistic.
689  * \since 12.0.0
690  *
691  * \param hash Container to operate upon.
692  * \param hash_node Container node linking object to.
693  *
694  * \return Nothing
695  */
696 static void hash_ao2_link_node_stat(struct ao2_container *hash, struct ao2_container_node *hash_node)
697 {
698  struct ao2_container_hash *self = (struct ao2_container_hash *) hash;
699  struct hash_bucket_node *node = (struct hash_bucket_node *) hash_node;
700  int i = node->my_bucket;
701 
702  ++self->buckets[i].elements;
703  if (self->buckets[i].max_elements < self->buckets[i].elements) {
704  self->buckets[i].max_elements = self->buckets[i].elements;
705  }
706 }
707 #endif /* defined(AO2_DEBUG) */
708 
709 #if defined(AO2_DEBUG)
710 /*!
711  * \internal
712  * \brief Decrement the hash container linked object statistic.
713  * \since 12.0.0
714  *
715  * \param hash Container to operate upon.
716  * \param hash_node Container node unlinking object from.
717  *
718  * \return Nothing
719  */
720 static void hash_ao2_unlink_node_stat(struct ao2_container *hash, struct ao2_container_node *hash_node)
721 {
722  struct ao2_container_hash *self = (struct ao2_container_hash *) hash;
723  struct hash_bucket_node *node = (struct hash_bucket_node *) hash_node;
724 
725  --self->buckets[node->my_bucket].elements;
726 }
727 #endif /* defined(AO2_DEBUG) */
728 
729 /*!
730  * \internal
731  *
732  * \brief Destroy this container.
733  * \since 12.0.0
734  *
735  * \param self Container to operate upon.
736  *
737  * \return Nothing
738  */
739 static void hash_ao2_destroy(struct ao2_container_hash *self)
740 {
741  int idx;
742 
743  /* Check that the container no longer has any nodes */
744  for (idx = self->n_buckets; idx--;) {
745  if (!AST_DLLIST_EMPTY(&self->buckets[idx].list)) {
746  ast_log(LOG_ERROR, "Node ref leak. Hash container still has nodes!\n");
747  ast_assert(0);
748  break;
749  }
750  }
751 }
752 
753 #if defined(AO2_DEBUG)
754 /*!
755  * \internal
756  * \brief Display contents of the specified container.
757  * \since 12.0.0
758  *
759  * \param self Container to dump.
760  * \param where User data needed by prnt to determine where to put output.
761  * \param prnt Print output callback function to use.
762  * \param prnt_obj Callback function to print the given object's key. (NULL if not available)
763  *
764  * \return Nothing
765  */
766 static void hash_ao2_dump(struct ao2_container_hash *self, void *where, ao2_prnt_fn *prnt, ao2_prnt_obj_fn *prnt_obj)
767 {
768 #define FORMAT "%6s, %16s, %16s, %16s, %16s, %s\n"
769 #define FORMAT2 "%6d, %16p, %16p, %16p, %16p, "
770 
771  int bucket;
772  int suppressed_buckets = 0;
773  struct hash_bucket_node *node;
774 
775  prnt(where, "Number of buckets: %d\n\n", self->n_buckets);
776 
777  prnt(where, FORMAT, "Bucket", "Node", "Prev", "Next", "Obj", "Key");
778  for (bucket = 0; bucket < self->n_buckets; ++bucket) {
779  node = AST_DLLIST_FIRST(&self->buckets[bucket].list);
780  if (node) {
781  suppressed_buckets = 0;
782  do {
783  prnt(where, FORMAT2,
784  bucket,
785  node,
786  AST_DLLIST_PREV(node, links),
787  AST_DLLIST_NEXT(node, links),
788  node->common.obj);
789  if (node->common.obj && prnt_obj) {
790  prnt_obj(node->common.obj, where, prnt);
791  }
792  prnt(where, "\n");
793 
794  node = AST_DLLIST_NEXT(node, links);
795  } while (node);
796  } else if (!suppressed_buckets) {
797  suppressed_buckets = 1;
798  prnt(where, "...\n");
799  }
800  }
801 
802 #undef FORMAT
803 #undef FORMAT2
804 }
805 #endif /* defined(AO2_DEBUG) */
806 
807 #if defined(AO2_DEBUG)
808 /*!
809  * \internal
810  * \brief Display statistics of the specified container.
811  * \since 12.0.0
812  *
813  * \param self Container to display statistics.
814  * \param where User data needed by prnt to determine where to put output.
815  * \param prnt Print output callback function to use.
816  *
817  * \note The container is already locked for reading.
818  *
819  * \return Nothing
820  */
821 static void hash_ao2_stats(struct ao2_container_hash *self, void *where, ao2_prnt_fn *prnt)
822 {
823 #define FORMAT "%10.10s %10.10s %10.10s\n"
824 #define FORMAT2 "%10d %10d %10d\n"
825 
826  int bucket;
827  int suppressed_buckets = 0;
828 
829  prnt(where, "Number of buckets: %d\n\n", self->n_buckets);
830 
831  prnt(where, FORMAT, "Bucket", "Objects", "Max");
832  for (bucket = 0; bucket < self->n_buckets; ++bucket) {
833  if (self->buckets[bucket].max_elements) {
834  suppressed_buckets = 0;
835  prnt(where, FORMAT2, bucket, self->buckets[bucket].elements,
836  self->buckets[bucket].max_elements);
837  } else if (!suppressed_buckets) {
838  suppressed_buckets = 1;
839  prnt(where, "...\n");
840  }
841  }
842 
843 #undef FORMAT
844 #undef FORMAT2
845 }
846 #endif /* defined(AO2_DEBUG) */
847 
848 #if defined(AO2_DEBUG)
849 /*!
850  * \internal
851  * \brief Perform an integrity check on the specified container.
852  * \since 12.0.0
853  *
854  * \param self Container to check integrity.
855  *
856  * \note The container is already locked for reading.
857  *
858  * \retval 0 on success.
859  * \retval -1 on error.
860  */
861 static int hash_ao2_integrity(struct ao2_container_hash *self)
862 {
863  int bucket_exp;
864  int bucket;
865  int count_obj;
866  int count_total_obj;
867  int count_total_node;
868  void *obj_last;
869  struct hash_bucket_node *node;
870  struct hash_bucket_node *prev;
871  struct hash_bucket_node *next;
872 
873  count_total_obj = 0;
874  count_total_node = 0;
875 
876  /* For each bucket in the container. */
877  for (bucket = 0; bucket < self->n_buckets; ++bucket) {
878  if (!AST_DLLIST_FIRST(&self->buckets[bucket].list)
879  && !AST_DLLIST_LAST(&self->buckets[bucket].list)) {
880  /* The bucket list is empty. */
881  continue;
882  }
883 
884  count_obj = 0;
885  obj_last = NULL;
886 
887  /* Check bucket list links and nodes. */
888  node = AST_DLLIST_LAST(&self->buckets[bucket].list);
889  if (!node) {
890  ast_log(LOG_ERROR, "Bucket %d list tail is NULL when it should not be!\n",
891  bucket);
892  return -1;
893  }
894  if (AST_DLLIST_NEXT(node, links)) {
895  ast_log(LOG_ERROR, "Bucket %d list tail node is not the last node!\n",
896  bucket);
897  return -1;
898  }
899  node = AST_DLLIST_FIRST(&self->buckets[bucket].list);
900  if (!node) {
901  ast_log(LOG_ERROR, "Bucket %d list head is NULL when it should not be!\n",
902  bucket);
903  return -1;
904  }
905  if (AST_DLLIST_PREV(node, links)) {
906  ast_log(LOG_ERROR, "Bucket %d list head node is not the first node!\n",
907  bucket);
908  return -1;
909  }
910  for (; node; node = next) {
911  /* Check backward link. */
912  prev = AST_DLLIST_PREV(node, links);
913  if (prev) {
914  if (prev == node) {
915  ast_log(LOG_ERROR, "Bucket %d list node's prev pointer points to itself!\n",
916  bucket);
917  return -1;
918  }
919  if (node != AST_DLLIST_NEXT(prev, links)) {
920  ast_log(LOG_ERROR, "Bucket %d list node's prev node does not link back!\n",
921  bucket);
922  return -1;
923  }
924  } else if (node != AST_DLLIST_FIRST(&self->buckets[bucket].list)) {
925  ast_log(LOG_ERROR, "Bucket %d backward list chain is broken!\n",
926  bucket);
927  return -1;
928  }
929 
930  /* Check forward link. */
931  next = AST_DLLIST_NEXT(node, links);
932  if (next) {
933  if (next == node) {
934  ast_log(LOG_ERROR, "Bucket %d list node's next pointer points to itself!\n",
935  bucket);
936  return -1;
937  }
938  if (node != AST_DLLIST_PREV(next, links)) {
939  ast_log(LOG_ERROR, "Bucket %d list node's next node does not link back!\n",
940  bucket);
941  return -1;
942  }
943  } else if (node != AST_DLLIST_LAST(&self->buckets[bucket].list)) {
944  ast_log(LOG_ERROR, "Bucket %d forward list chain is broken!\n",
945  bucket);
946  return -1;
947  }
948 
949  if (bucket != node->my_bucket) {
950  ast_log(LOG_ERROR, "Bucket %d node claims to be in bucket %d!\n",
951  bucket, node->my_bucket);
952  return -1;
953  }
954 
955  ++count_total_node;
956  if (!node->common.obj) {
957  /* Node is empty. */
958  continue;
959  }
960  ++count_obj;
961 
962  /* Check container hash key for expected bucket. */
963  bucket_exp = abs(self->hash_fn(node->common.obj, OBJ_SEARCH_OBJECT)
964  % self->n_buckets);
965  if (bucket != bucket_exp) {
966  ast_log(LOG_ERROR, "Bucket %d node hashes to bucket %d!\n",
967  bucket, bucket_exp);
968  return -1;
969  }
970 
971  /* Check sort if configured. */
972  if (self->common.sort_fn) {
973  if (obj_last
974  && self->common.sort_fn(obj_last, node->common.obj, OBJ_SEARCH_OBJECT) > 0) {
975  ast_log(LOG_ERROR, "Bucket %d nodes out of sorted order!\n",
976  bucket);
977  return -1;
978  }
979  obj_last = node->common.obj;
980  }
981  }
982 
983  /* Check bucket obj count statistic. */
984  if (count_obj != self->buckets[bucket].elements) {
985  ast_log(LOG_ERROR, "Bucket %d object count of %d does not match stat of %d!\n",
986  bucket, count_obj, self->buckets[bucket].elements);
987  return -1;
988  }
989 
990  /* Accumulate found object counts. */
991  count_total_obj += count_obj;
992  }
993 
994  /* Check total obj count. */
995  if (count_total_obj != ao2_container_count(&self->common)) {
997  "Total object count of %d does not match ao2_container_count() of %d!\n",
998  count_total_obj, ao2_container_count(&self->common));
999  return -1;
1000  }
1001 
1002  /* Check total node count. */
1003  if (count_total_node != self->common.nodes) {
1004  ast_log(LOG_ERROR, "Total node count of %d does not match stat of %d!\n",
1005  count_total_node, self->common.nodes);
1006  return -1;
1007  }
1008 
1009  return 0;
1010 }
1011 #endif /* defined(AO2_DEBUG) */
1012 
1013 /*! Hash container virtual method table. */
1014 static const struct ao2_container_methods v_table_hash = {
1022 #if defined(AO2_DEBUG)
1023  .link_stat = hash_ao2_link_node_stat,
1024  .unlink_stat = hash_ao2_unlink_node_stat,
1025  .dump = (ao2_container_display) hash_ao2_dump,
1026  .stats = (ao2_container_statistics) hash_ao2_stats,
1027  .integrity = (ao2_container_integrity) hash_ao2_integrity,
1028 #endif /* defined(AO2_DEBUG) */
1029 };
1030 
1031 /*!
1032  * \brief always zero hash function
1033  *
1034  * it is convenient to have a hash function that always returns 0.
1035  * This is basically used when we want to have a container that is
1036  * a simple linked list.
1037  *
1038  * \returns 0
1039  */
1040 static int hash_zero(const void *user_obj, const int flags)
1041 {
1042  return 0;
1043 }
1044 
1045 /*!
1046  * \brief Initialize a hash container with the desired number of buckets.
1047  *
1048  * \param self Container to initialize.
1049  * \param options Container behaviour options (See enum ao2_container_opts)
1050  * \param n_buckets Number of buckets for hash
1051  * \param hash_fn Pointer to a function computing a hash value.
1052  * \param sort_fn Pointer to a sort function.
1053  * \param cmp_fn Pointer to a compare function used by ao2_find.
1054  *
1055  * \return A pointer to a struct container.
1056  */
1058  struct ao2_container_hash *self, unsigned int options, unsigned int n_buckets,
1060 {
1061  if (!self) {
1062  return NULL;
1063  }
1064 
1065  self->common.v_table = &v_table_hash;
1066  self->common.sort_fn = sort_fn;
1067  self->common.cmp_fn = cmp_fn;
1068  self->common.options = options;
1069  self->hash_fn = hash_fn ? hash_fn : hash_zero;
1070  self->n_buckets = n_buckets;
1071 
1072 #ifdef AO2_DEBUG
1073  ast_atomic_fetchadd_int(&ao2.total_containers, 1);
1074 #endif /* defined(AO2_DEBUG) */
1075 
1076  return (struct ao2_container *) self;
1077 }
1078 
1079 struct ao2_container *__ao2_container_alloc_hash(unsigned int ao2_options,
1080  unsigned int container_options, unsigned int n_buckets, ao2_hash_fn *hash_fn,
1082  const char *tag, const char *file, int line, const char *func)
1083 {
1084  unsigned int num_buckets;
1085  size_t container_size;
1086  struct ao2_container_hash *self;
1087 
1088  num_buckets = hash_fn ? n_buckets : 1;
1089  container_size = sizeof(struct ao2_container_hash) + num_buckets * sizeof(struct hash_bucket);
1090 
1091  self = __ao2_alloc(container_size, container_destruct, ao2_options,
1092  tag ?: __PRETTY_FUNCTION__, file, line, func);
1093  return hash_ao2_container_init(self, container_options, num_buckets, hash_fn,
1094  sort_fn, cmp_fn);
1095 }
1096 
1097 struct ao2_container *__ao2_container_alloc_list(unsigned int ao2_options,
1098  unsigned int container_options, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn,
1099  const char *tag, const char *file, int line, const char *func)
1100 {
1101  return __ao2_container_alloc_hash(ao2_options, container_options, 1, NULL,
1102  sort_fn, cmp_fn, tag, file, line, func);
1103 }
#define AST_DLLIST_TRAVERSE_SAFE_BEGIN(head, var, field)
Loops safely over (traverses) the entries in a list.
Definition: dlinkedlists.h:848
Definition: test_heap.c:38
struct ao2_container common
Items common to all containers.
Definition: astobj2_hash.c:70
struct ao2_container_node *(* ao2_iterator_next_fn)(struct ao2_container *self, struct ao2_container_node *prev, enum ao2_iterator_flags flags)
Find the next non-empty iteration node in the container.
Asterisk main include file. File version handling, generic pbx functions.
int ao2_container_count(struct ao2_container *c)
Returns the number of elements in a container.
#define __is_ao2_object(user_data, file, line, func)
#define AST_DLLIST_INSERT_HEAD(head, elm, field)
Inserts a list entry at the head of a list.
The arg parameter is a search key, but is not an object.
Definition: astobj2.h:1105
struct ao2_container * __ao2_container_alloc_list(unsigned int ao2_options, unsigned int container_options, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn, const char *tag, const char *file, int line, const char *func)
#define __container_unlink_node(node, flags)
void container_destruct(void *_c)
Common, private definitions for astobj2.
static void hash_ao2_destroy(struct ao2_container_hash *self)
Definition: astobj2_hash.c:739
Allow objects with duplicate keys in container.
Definition: astobj2.h:1185
#define FORMAT2
enum ao2_container_insert(* ao2_container_insert_fn)(struct ao2_container *self, struct ao2_container_node *node)
Insert a node into this container.
struct ao2_container * __ao2_container_alloc_hash(unsigned int ao2_options, unsigned int container_options, unsigned int n_buckets, ao2_hash_fn *hash_fn, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn, const char *tag, const char *file, int line, const char *func)
static struct hash_bucket_node * hash_ao2_new_node(struct ao2_container_hash *self, void *obj_new, const char *tag, const char *file, int line, const char *func)
Definition: astobj2_hash.c:208
void * __ao2_alloc(size_t data_size, ao2_destructor_fn destructor_fn, unsigned int options, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
Definition: astobj2.c:765
int() ao2_sort_fn(const void *obj_left, const void *obj_right, int flags)
Type of generic container sort function.
Definition: astobj2.h:1280
#define AST_DLLIST_TRAVERSE_BACKWARDS_SAFE_BEGIN(head, var, field)
Loops safely over (traverses) the entries in a list.
Definition: dlinkedlists.h:887
Assume that the ao2_container is already locked.
Definition: astobj2.h:1067
int(* ao2_container_integrity)(struct ao2_container *self)
Perform an integrity check on the specified container.
#define ao2_alloc_options(data_size, destructor_fn, options)
Definition: astobj2.h:406
static void hash_ao2_node_destructor(void *v_doomed)
Definition: astobj2_hash.c:145
#define ast_assert(a)
Definition: utils.h:710
#define SWAP(a, b)
Definition: utils.h:230
ao2_container_find_first_fn traverse_first
static enum ao2_container_insert hash_ao2_insert_node(struct ao2_container_hash *self, struct hash_bucket_node *node)
Definition: astobj2_hash.c:239
search_flags
Flags passed to ao2_callback_fn(), ao2_hash_fn(), and ao2_sort_fn() to modify behaviour.
Definition: astobj2.h:1038
#define NULL
Definition: resample.c:96
#define AST_DLLIST_INSERT_AFTER_CURRENT(elm, field)
Inserts a list node after the current node during a traversal.
Definition: dlinkedlists.h:722
int ast_atomic_fetchadd_int(volatile int *p, int v)
Atomically add v to *p and return the previous value of *p.
Definition: lock.h:755
Insert objects at the beginning of the container. (Otherwise it is the opposite; insert at the end...
Definition: astobj2.h:1176
Utility functions.
void() ao2_prnt_fn(void *where, const char *fmt,...)
Print output.
Definition: astobj2.h:1442
Generic container node.
#define is_ao2_object(user_data)
Traverse in ascending order (First to last container object)
Definition: astobj2.h:1125
int ao2_container_check(struct ao2_container *self, enum search_flags flags)
Perform an integrity check on the specified container.
static struct ao2_container * hash_ao2_container_init(struct ao2_container_hash *self, unsigned int options, unsigned int n_buckets, ao2_hash_fn *hash_fn, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn)
Initialize a hash container with the desired number of buckets.
int __ao2_ref(void *o, int delta, const char *tag, const char *file, int line, const char *func)
Definition: astobj2.c:498
#define AST_DLLIST_INSERT_TAIL(head, elm, field)
Appends a list entry to the tail of a list.
int() ao2_callback_fn(void *obj, void *arg, int flags)
Type of a generic callback function.
Definition: astobj2.h:1230
#define ast_log
Definition: astobj2.c:42
The arg parameter is a partial search key similar to OBJ_SEARCH_KEY.
Definition: astobj2.h:1120
#define AST_DLLIST_NEXT(elm, field)
Returns the next entry in the list after the given entry.
Definition: dlinkedlists.h:445
A set of macros to manage doubly-linked lists.
#define AST_DLLIST_HEAD_NOLOCK(name, type)
Defines a structure to be used to hold a list of specified type (with no lock).
Definition: dlinkedlists.h:211
static int hash_zero(const void *user_obj, const int flags)
always zero hash function
struct ao2_container_node *(* ao2_container_find_first_fn)(struct ao2_container *self, enum search_flags flags, void *arg, void *v_state)
Find the first container node in a traversal.
The ao2 container objects with duplicate keys option field mask.
Definition: astobj2.h:1181
#define ao2_ref(o, delta)
Definition: astobj2.h:464
#define AO2_DEVMODE_STAT(stat)
Traverse in descending order (Last to first container object)
Definition: astobj2.h:1127
struct hash_bucket::@335 list
ao2_sort_fn * sort_fn
Definition: astobj2_hash.c:81
#define AST_DLLIST_INSERT_BEFORE_CURRENT(elm, field)
Inserts a list node before the current node during a traversal.
Definition: dlinkedlists.h:695
unsigned int descending
Definition: astobj2_hash.c:91
struct ao2_container_node common
Items common to all container nodes.
Definition: astobj2_hash.c:42
void(* ao2_container_destroy_fn)(struct ao2_container *self)
Destroy this container.
void(* ao2_container_statistics)(struct ao2_container *self, void *where, ao2_prnt_fn *prnt)
Display statistics of the specified container.
#define LOG_ERROR
Definition: logger.h:285
int() ao2_hash_fn(const void *obj, int flags)
Definition: astobj2.h:1262
static struct hash_bucket_node * hash_ao2_iterator_next(struct ao2_container_hash *self, struct hash_bucket_node *node, enum ao2_iterator_flags flags)
Definition: astobj2_hash.c:613
ao2_iterator_next_fn iterator_next
Traverse in pre-order (Node then children, for tree container)
Definition: astobj2.h:1136
#define FORMAT
static struct ao2_container * hash_ao2_alloc_empty_clone(struct ao2_container_hash *self, const char *tag, const char *file, int line, const char *func)
Definition: astobj2_hash.c:116
enum search_flags flags
Definition: astobj2_hash.c:89
struct hash_bucket_node::@334 links
static const struct ao2_container_methods v_table_hash
unsigned int destroying
TRUE if the container is being destroyed.
#define AST_DLLIST_EMPTY(head)
Checks whether the specified list contains any entries.
Definition: dlinkedlists.h:468
Prototypes for public functions only of internal interest,.
#define AO2_TRAVERSAL_STATE_SIZE
ao2_hash_fn * hash_fn
Definition: astobj2_hash.c:71
#define AST_DLLIST_TRAVERSE_SAFE_END
Closes a safe loop traversal block.
Definition: dlinkedlists.h:912
The arg parameter is an object of the same type.
Definition: astobj2.h:1091
Replace objects with duplicate keys in container.
Definition: astobj2.h:1215
#define AST_DLLIST_TRAVERSE_BACKWARDS_SAFE_END
Closes a safe loop traversal block.
Definition: dlinkedlists.h:920
#define abs(x)
Definition: f2c.h:195
Traverse in post-order (Children then node, for tree container)
Definition: astobj2.h:1145
unsigned int ao2_options_get(void *obj)
Retrieve the ao2 options used to create the object.
Definition: astobj2.c:778
#define AST_DLLIST_PREV(elm, field)
Returns the previous entry in the list before the given entry.
Definition: dlinkedlists.h:456
Common, private definitions for astobj2 containers.
struct ao2_container *(* ao2_container_alloc_empty_clone_fn)(struct ao2_container *self, const char *tag, const char *file, int line, const char *func)
Create an empty copy of this container.
enum ao2_lock_req __adjust_lock(void *user_data, enum ao2_lock_req lock_how, int keep_stronger)
Definition: astobj2.c:425
#define AST_DLLIST_REMOVE(head, elm, field)
Removes a specific entry from a list.
Reject objects with duplicate keys in container.
Definition: astobj2.h:1192
Generic container type.
static struct test_options options
Search option field mask.
Definition: astobj2.h:1076
static struct hash_bucket_node * hash_ao2_find_first(struct ao2_container_hash *self, enum search_flags flags, void *arg, struct hash_traversal_state *state)
Definition: astobj2_hash.c:335
void() ao2_prnt_obj_fn(void *v_obj, void *where, ao2_prnt_fn *prnt)
Print object key.
Definition: astobj2.h:1454
struct ao2_container * my_container
struct hash_bucket buckets[0]
Definition: astobj2_hash.c:75
static struct hash_bucket_node * hash_ao2_find_next(struct ao2_container_hash *self, struct hash_traversal_state *state, struct hash_bucket_node *prev)
Definition: astobj2_hash.c:483
ao2_iterator_flags
Definition: astobj2.h:1855
struct ao2_container_node *(* ao2_container_new_node_fn)(struct ao2_container *self, void *obj_new, const char *tag, const char *file, int line, const char *func)
Create a new container node.
#define AST_DLLIST_FIRST(head)
Returns the first entry contained in a list.
Definition: dlinkedlists.h:421
ao2_container_alloc_empty_clone_fn alloc_empty_clone
Create an empty copy of this container.
Reject duplicate objects in container.
Definition: astobj2.h:1205
ao2_callback_fn * cmp_fn
ao2_container_new_node_fn new_node
Traverse order option field mask.
Definition: astobj2.h:1123
#define AST_DLLIST_LAST(head)
Returns the last entry contained in a list.
Definition: dlinkedlists.h:430
struct ao2_container_node *(* ao2_container_find_next_fn)(struct ao2_container *self, void *v_state, struct ao2_container_node *prev)
Find the next container node in a traversal.
#define AST_DLLIST_ENTRY(type)
Declare previous/forward links inside a list entry.
Definition: dlinkedlists.h:412
void(* ao2_container_display)(struct ao2_container *self, void *where, ao2_prnt_fn *prnt, ao2_prnt_obj_fn *prnt_obj)
Display contents of the specified container.