Asterisk - The Open Source Telephony Project  GIT-master-a24979a
astobj2.h
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1 /*
2  * astobj2 - replacement containers for asterisk data structures.
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 #ifndef _ASTERISK_ASTOBJ2_H
18 #define _ASTERISK_ASTOBJ2_H
19 
20 #include "asterisk/compat.h"
21 #include "asterisk/lock.h"
22 #include "asterisk/linkedlists.h"
23 #include "asterisk/inline_api.h"
24 
25 /*! \file
26  * \ref AstObj2
27  *
28  * \page AstObj2 Object Model implementing objects and containers.
29 
30 This module implements an abstraction for objects (with locks and
31 reference counts), and containers for these user-defined objects,
32 also supporting locking, reference counting and callbacks.
33 
34 The internal implementation of objects and containers is opaque to the user,
35 so we can use different data structures as needs arise.
36 
37 \section AstObj2_UsageObjects USAGE - OBJECTS
38 
39 An ao2 object is a block of memory that the user code can access,
40 and for which the system keeps track (with a bit of help from the
41 programmer) of the number of references around. When an object has
42 no more references (refcount == 0), it is destroyed, by first
43 invoking whatever 'destructor' function the programmer specifies
44 (it can be NULL if none is necessary), and then freeing the memory.
45 This way objects can be shared without worrying who is in charge
46 of freeing them.
47 As an additional feature, ao2 objects are associated to individual
48 locks.
49 
50 Creating an object requires the size of the object and
51 a pointer to the destructor function:
52 
53  struct foo *o;
54 
55  o = ao2_alloc(sizeof(struct foo), my_destructor_fn);
56 
57 The value returned points to the user-visible portion of the objects
58 (user-data), but is also used as an identifier for all object-related
59 operations such as refcount and lock manipulations.
60 
61 On return from ao2_alloc():
62 
63  - the object has a refcount = 1;
64  - the memory for the object is allocated dynamically and zeroed;
65  - we cannot realloc() the object itself;
66  - we cannot call free(o) to dispose of the object. Rather, we
67  tell the system that we do not need the reference anymore:
68 
69  ao2_ref(o, -1)
70 
71  causing the destructor to be called (and then memory freed) when
72  the refcount goes to 0.
73 
74 ao2_ref(o, +1) can be used to modify the refcount on the
75 object in case we want to pass it around.
76 
77 ao2_lock(obj), ao2_unlock(obj), ao2_trylock(obj) can be used
78 to manipulate the lock associated with the object.
79 
80 
81 \section AstObj2_UsageContainers USAGE - CONTAINERS
82 
83 An ao2 container is an abstract data structure where we can store
84 ao2 objects, search them (hopefully in an efficient way), and iterate
85 or apply a callback function to them. A container is just an ao2 object
86 itself.
87 
88 A container must first be allocated, specifying the initial
89 parameters. At the moment, this is done as follows:
90 
91  <b>Sample Usage:</b>
92  \code
93 
94  struct ao2_container *c;
95 
96  c = ao2_container_alloc_hash(AO2_ALLOC_OPT_LOCK_MUTEX, 0, MAX_BUCKETS,
97  my_hash_fn, NULL, my_cmp_fn);
98  \endcode
99 
100 where
101 
102 - MAX_BUCKETS is the number of buckets in the hash table,
103 - my_hash_fn() is the (user-supplied) function that returns a
104  hash key for the object (further reduced modulo MAX_BUCKETS
105  by the container's code);
106 - my_cmp_fn() is the default comparison function used when doing
107  searches on the container,
108 
109 A container knows little or nothing about the objects it stores,
110 other than the fact that they have been created by ao2_alloc().
111 All knowledge of the (user-defined) internals of the objects
112 is left to the (user-supplied) functions passed as arguments
113 to ao2_container_alloc_hash().
114 
115 If we want to insert an object in a container, we should
116 initialize its fields -- especially, those used by my_hash_fn() --
117 to compute the bucket to use.
118 Once done, we can link an object to a container with
119 
120  ao2_link(c, o);
121 
122 The function returns NULL in case of errors (and the object
123 is not inserted in the container). Other values mean success
124 (we are not supposed to use the value as a pointer to anything).
125 Linking an object to a container increases its refcount by 1
126 automatically.
127 
128 \note While an object o is in a container, we expect that
129 my_hash_fn(o) will always return the same value. The function
130 does not lock the object to be computed, so modifications of
131 those fields that affect the computation of the hash should
132 be done by extracting the object from the container, and
133 re-inserting it after the change (this is not terribly expensive).
134 
135 \note A container with a single buckets is effectively a linked
136 list. However there is no ordering among elements.
137 
138 - \ref AstObj2_Containers
139 - \ref astobj2.h All documentation for functions and data structures
140 
141  */
142 
143 /*
144 \note DEBUGGING REF COUNTS BIBLE:
145 An interface to help debug refcounting is provided
146 in this package. It is dependent on the refdebug being enabled in
147 asterisk.conf.
148 
149 Each of the reference manipulations will generate one line of output in the refs
150 log file. These lines look like this:
151 ...
152 0x8756f00,+1,1234,chan_sip.c,22240,load_module,**constructor**,allocate users
153 0x86e3408,+1,1234,chan_sip.c,22241,load_module,**constructor**,allocate peers
154 0x86dd380,+1,1234,chan_sip.c,22242,load_module,**constructor**,allocate peers_by_ip
155 0x822d020,+1,1234,chan_sip.c,22243,load_module,**constructor**,allocate dialogs
156 0x8930fd8,+1,1234,chan_sip.c,20025,build_peer,**constructor**,allocate a peer struct
157 0x8930fd8,+1,1234,chan_sip.c,21467,reload_config,1,link peer into peer table
158 0x8930fd8,-1,1234,chan_sip.c,2370,unref_peer,2,unref_peer: from reload_config
159 0x89318b0,1,5678,chan_sip.c,20025,build_peer,**constructor**,allocate a peer struct
160 0x89318b0,+1,5678,chan_sip.c,21467,reload_config,1,link peer into peer table
161 0x89318b0,-1,1234,chan_sip.c,2370,unref_peer,2,unref_peer: from reload_config
162 0x8930218,+1,1234,chan_sip.c,20025,build_peer,**constructor**,allocate a peer struct
163 0x8930218,+1,1234,chan_sip.c,21539,reload_config,1,link peer into peers table
164 0x868c040,-1,1234,chan_sip.c,2424,dialog_unlink_all,2,unset the relatedpeer->call field in tandem with relatedpeer field itself
165 0x868c040,-1,1234,chan_sip.c,2443,dialog_unlink_all,1,Let's unbump the count in the unlink so the poor pvt can disappear if it is time
166 0x868c040,-1,1234,chan_sip.c,2443,dialog_unlink_all,**destructor**,Let's unbump the count in the unlink so the poor pvt can disappear if it is time
167 0x8cc07e8,-1,1234,chan_sip.c,2370,unref_peer,3,unsetting a dialog relatedpeer field in sip_destroy
168 0x8cc07e8,+1,1234,chan_sip.c,3876,find_peer,2,ao2_find in peers table
169 0x8cc07e8,-1,1234,chan_sip.c,2370,unref_peer,3,unref_peer, from sip_devicestate, release ref from find_peer
170 ...
171 
172 This uses a comma delineated format. The columns in the format are as
173 follows:
174 - The first column is the object address.
175 - The second column reflects how the operation affected the ref count
176  for that object. A change in the ref count is reflected either as
177  an increment (+) or decrement (-), as well as the amount it changed
178  by.
179 - The third column is the ID of the thread that modified the reference
180  count.
181 - The fourth column is the source file that the change in reference was
182  issued from.
183 - The fifth column is the line number of the source file that the ref
184  change was issued from.
185 - The sixth column is the name of the function that the ref change was
186  issued from.
187 - The seventh column indicates either (a) construction of the object via
188  the special tag **constructor**; (b) destruction of the object via
189  the special tag **destructor**; (c) the previous reference count
190  prior to this reference change.
191 - The eighth column is a special tag added by the developer to provide
192  context for the ref change. Note that any subsequent columns are
193  considered to be part of this tag.
194 
195 Sometimes you have some helper functions to do object create/ref/unref
196 operations. Using these normally hides the place where these
197 functions were called. To get the location where these functions
198 were called to appear in refs log, you can do this sort of thing:
199 
200 #define my_t_alloc(data,tag) my_alloc_debug((data), tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
201 #define my_alloc(data) my_t_alloc((data), NULL)
202 
203 static struct mydata *my_alloc_debug(void *data,
204  const char *tag, const char *file, int line, const char *func)
205 {
206  struct mydata *p;
207 
208  p = __ao2_alloc(sizeof(*p), NULL, AO2_ALLOC_OPT_LOCK_MUTEX, tag, file, line, func);
209  if (p) {
210  p->data = data;
211  }
212  return p;
213 }
214 
215 To find out why objects are not destroyed (a common bug), you can
216 enable refdebug in asterisk.conf. Run asterisk, exit with "core stop gracefully".
217 This should result in every object being destroyed.
218 
219 Then, you can "sort -k 1 {AST_LOG_DIR}/refs > x1" to get a sorted list of
220 all the objects, or you can use "contrib/script/refcounter.py" to scan
221 the file for you and output any problems it finds.
222 
223 The above may seem astronomically more work than it is worth to debug
224 reference counts, which may be true in "simple" situations, but for
225 more complex situations, it is easily worth 100 times this effort to
226 help find problems.
227 
228 To debug, pair all calls so that each call that increments the
229 refcount is paired with a corresponding call that decrements the
230 count for the same reason. Hopefully, you will be left with one
231 or more unpaired calls. This is where you start your search!
232 
233 For instance, here is an example of this for a dialog object in
234 chan_sip, that was not getting destroyed, after I moved the lines around
235 to pair operations:
236 
237  0x83787a0,+1,1234,chan_sip.c,5733,sip_alloc,**constructor**,(allocate a dialog(pvt) struct)
238  0x83787a0,-1,1234,chan_sip.c,19173,sip_poke_peer,4,(unref dialog at end of sip_poke_peer, obtained from sip_alloc, just before it goes out of scope)
239 
240  0x83787a0,+1,1234,chan_sip.c,5854,sip_alloc,1,(link pvt into dialogs table)
241  0x83787a0,-1,1234,chan_sip.c,19150,sip_poke_peer,3,(About to change the callid -- remove the old name)
242  0x83787a0,+1,1234,chan_sip.c,19152,sip_poke_peer,2,(Linking in under new name)
243  0x83787a0,-1,1234,chan_sip.c,2399,dialog_unlink_all,5,(unlinking dialog via ao2_unlink)
244 
245  0x83787a0,+1,1234,chan_sip.c,19130,sip_poke_peer,2,(copy sip alloc from p to peer->call)
246 
247 
248  0x83787a0,+1,1234,chan_sip.c,2996,__sip_reliable_xmit,3,(__sip_reliable_xmit: setting pkt->owner)
249  0x83787a0,-1,1234,chan_sip.c,2425,dialog_unlink_all,4,(remove all current packets in this dialog, and the pointer to the dialog too as part of __sip_destroy)
250 
251  0x83787a0,+1,1234,chan_sip.c,22356,unload_module,4,(iterate thru dialogs)
252  0x83787a0,-1,1234,chan_sip.c,22359,unload_module,5,(toss dialog ptr from iterator_next)
253 
254 
255  0x83787a0,+1,1234,chan_sip.c,22373,unload_module,3,(iterate thru dialogs)
256  0x83787a0,-1,1234,chan_sip.c,22375,unload_module,2,(throw away iterator result)
257 
258  0x83787a0,+1,1234,chan_sip.c,2397,dialog_unlink_all,4,(Let's bump the count in the unlink so it doesn't accidentally become dead before we are done)
259  0x83787a0,-1,1234,chan_sip.c,2436,dialog_unlink_all,3,(Let's unbump the count in the unlink so the poor pvt can disappear if it is time)
260 
261 As you can see, only one unbalanced operation is in the list, a ref count increment when
262 the peer->call was set, but no corresponding decrement was made...
263 
264 Hopefully this helps you narrow your search and find those bugs.
265 
266 THE ART OF REFERENCE COUNTING
267 (by Steve Murphy)
268 SOME TIPS for complicated code, and ref counting:
269 
270 1. Theoretically, passing a refcounted object pointer into a function
271 call is an act of copying the reference, and could be refcounted.
272 But, upon examination, this sort of refcounting will explode the amount
273 of code you have to enter, and for no tangible benefit, beyond
274 creating more possible failure points/bugs. It will even
275 complicate your code and make debugging harder, slow down your program
276 doing useless increments and decrements of the ref counts.
277 
278 2. It is better to track places where a ref counted pointer
279 is copied into a structure or stored. Make sure to decrement the refcount
280 of any previous pointer that might have been there, if setting
281 this field might erase a previous pointer. ao2_find and iterate_next
282 internally increment the ref count when they return a pointer, so
283 you need to decrement the count before the pointer goes out of scope.
284 
285 3. Any time you decrement a ref count, it may be possible that the
286 object will be destroyed (freed) immediately by that call. If you
287 are destroying a series of fields in a refcounted object, and
288 any of the unref calls might possibly result in immediate destruction,
289 you can first increment the count to prevent such behavior, then
290 after the last test, decrement the pointer to allow the object
291 to be destroyed, if the refcount would be zero.
292 
293 Example:
294 
295  dialog_ref(dialog, "Let's bump the count in the unlink so it doesn't accidentally become dead before we are done");
296 
297  ao2_t_unlink(dialogs, dialog, "unlinking dialog via ao2_unlink");
298 
299  *//* Unlink us from the owner (channel) if we have one *//*
300  if (dialog->owner) {
301  if (lockowner) {
302  ast_channel_lock(dialog->owner);
303  }
304  ast_debug(1, "Detaching from channel %s\n", dialog->owner->name);
305  dialog->owner->tech_pvt = dialog_unref(dialog->owner->tech_pvt, "resetting channel dialog ptr in unlink_all");
306  if (lockowner) {
307  ast_channel_unlock(dialog->owner);
308  }
309  }
310  if (dialog->registry) {
311  if (dialog->registry->call == dialog) {
312  dialog->registry->call = dialog_unref(dialog->registry->call, "nulling out the registry's call dialog field in unlink_all");
313  }
314  dialog->registry = registry_unref(dialog->registry, "delete dialog->registry");
315  }
316  ...
317  dialog_unref(dialog, "Let's unbump the count in the unlink so the poor pvt can disappear if it is time");
318 
319 In the above code, the ao2_t_unlink could end up destroying the dialog
320 object; if this happens, then the subsequent usages of the dialog
321 pointer could result in a core dump. So, we 'bump' the
322 count upwards before beginning, and then decrementing the count when
323 we are finished. This is analogous to 'locking' or 'protecting' operations
324 for a short while.
325 
326 4. One of the most insidious problems I've run into when converting
327 code to do ref counted automatic destruction, is in the destruction
328 routines. Where a "destroy" routine had previously been called to
329 get rid of an object in non-refcounted code, the new regime demands
330 that you tear that "destroy" routine into two pieces, one that will
331 tear down the links and 'unref' them, and the other to actually free
332 and reset fields. A destroy routine that does any reference deletion
333 for its own object, will never be called. Another insidious problem
334 occurs in mutually referenced structures. As an example, a dialog contains
335 a pointer to a peer, and a peer contains a pointer to a dialog. Watch
336 out that the destruction of one doesn't depend on the destruction of the
337 other, as in this case a dependency loop will result in neither being
338 destroyed!
339 
340 Given the above, you should be ready to do a good job!
341 
342 murf
343 
344 */
345 
346 
347 
348 /*!
349  * \brief Typedef for an object destructor.
350  *
351  * \param vdoomed Object to destroy.
352  *
353  * \details
354  * This is called just before freeing the memory for the object.
355  * It is passed a pointer to the user-defined data of the
356  * object.
357  */
358 typedef void (*ao2_destructor_fn)(void *vdoomed);
359 
360 /*! \brief Options available when allocating an ao2 object. */
362  /*! The ao2 object has a recursive mutex lock associated with it. */
364  /*! The ao2 object has a non-recursive read/write lock associated with it. */
366  /*! The ao2 object has no lock associated with it. */
368  /*! The ao2 object locking option field mask. */
370  /*!
371  * \internal The ao2 object uses a separate object for locking.
372  *
373  * \note This option is used internally by ao2_alloc_with_lockobj and
374  * should never be passed directly to ao2_alloc.
375  */
377  /*! The ao2 object will not record any REF_DEBUG entries */
379 };
380 
381 /*!
382  * \brief Allocate and initialize an object.
383  *
384  * \param data_size The sizeof() of the user-defined structure.
385  * \param destructor_fn The destructor function (can be NULL)
386  * \param options The ao2 object options (See enum ao2_alloc_opts)
387  * \param debug_msg An ao2 object debug tracing message.
388  * \return A pointer to user-data.
389  *
390  * \details
391  * Allocates a struct astobj2 with sufficient space for the
392  * user-defined structure.
393  * \note
394  * - storage is zeroed; XXX maybe we want a flag to enable/disable this.
395  * - the refcount of the object just created is 1
396  * - the returned pointer cannot be free()'d or realloc()'ed;
397  * rather, we just call ao2_ref(o, -1);
398  *
399  * @{
400  */
401 
402 #define ao2_t_alloc_options(data_size, destructor_fn, options, debug_msg) \
403  __ao2_alloc((data_size), (destructor_fn), (options), (debug_msg), __FILE__, __LINE__, __PRETTY_FUNCTION__)
404 #define ao2_alloc_options(data_size, destructor_fn, options) \
405  __ao2_alloc((data_size), (destructor_fn), (options), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
406 
407 #define ao2_t_alloc(data_size, destructor_fn, debug_msg) \
408  __ao2_alloc((data_size), (destructor_fn), AO2_ALLOC_OPT_LOCK_MUTEX, (debug_msg), __FILE__, __LINE__, __PRETTY_FUNCTION__)
409 #define ao2_alloc(data_size, destructor_fn) \
410  __ao2_alloc((data_size), (destructor_fn), AO2_ALLOC_OPT_LOCK_MUTEX, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
411 
412 void *__ao2_alloc(size_t data_size, ao2_destructor_fn destructor_fn, unsigned int options,
413  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
414 
415 /*! @} */
416 
417 /*!
418  * \since 14.1.0
419  * \brief Allocate and initialize an object with separate locking.
420  *
421  * \param data_size The sizeof() of the user-defined structure.
422  * \param destructor_fn The destructor function (can be NULL)
423  * \param lockobj A separate ao2 object that will provide locking.
424  * \param tag An ao2 object debug tracing message.
425  * \return A pointer to user-data.
426  *
427  * \see \ref ao2_alloc for additional details.
428  *
429  * \note lockobj must be a valid AO2 object.
430  */
431 #define ao2_alloc_with_lockobj(data_size, destructor_fn, lockobj, tag) \
432  __ao2_alloc_with_lockobj((data_size), (destructor_fn), (lockobj), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
433 
434 void *__ao2_alloc_with_lockobj(size_t data_size, ao2_destructor_fn destructor_fn, void *lockobj,
435  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
436 
437 /*! \brief
438  * Reference/unreference an object and return the old refcount.
439  *
440  * \param o A pointer to the object
441  * \param delta Value to add to the reference counter.
442  * \return The value of the reference counter before the operation.
443  *
444  * Increase/decrease the reference counter according
445  * the value of delta.
446  *
447  * If the refcount goes to zero, the object is destroyed.
448  *
449  * \note The object must not be locked by the caller of this function, as
450  * it is invalid to try to unlock it after releasing the reference.
451  *
452  * \note if we know the pointer to an object, it is because we
453  * have a reference count to it, so the only case when the object
454  * can go away is when we release our reference, and it is
455  * the last one in existence.
456  *
457  * @{
458  */
459 #define ao2_ref(o,delta) __ao2_ref((o), (delta), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
460 #define ao2_t_ref(o,delta,tag) __ao2_ref((o), (delta), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
461 
462 /*!
463  * \brief Retrieve the ao2 options used to create the object.
464  * \param obj pointer to the (user-defined part) of an object.
465  * \return options from enum ao2_alloc_opts.
466  */
467 unsigned int ao2_options_get(void *obj);
468 
469 /*!
470  * \since 12
471  * \brief Bump refcount on an AO2 object by one, returning the object.
472  *
473  * This is useful for inlining a ref bump, and you don't care about the ref
474  * count. Also \c NULL safe, for even more convenience.
475  *
476  * \param obj AO2 object to bump the refcount on.
477  *
478  * \return The given \a obj pointer.
479  */
480 #define ao2_bump(obj) \
481  ao2_t_bump((obj), NULL)
482 
483 #define ao2_t_bump(obj, tag) \
484  ({ \
485  typeof(obj) __obj_ ## __LINE__ = (obj); \
486  if (__obj_ ## __LINE__) { \
487  ao2_t_ref(__obj_ ## __LINE__, +1, (tag)); \
488  } \
489  __obj_ ## __LINE__; \
490  })
491 
492 int __ao2_ref(void *o, int delta, const char *tag, const char *file, int line, const char *func);
493 
494 /*!
495  * \since 12.4.0
496  * \brief Replace one object reference with another cleaning up the original.
497  *
498  * \param dst Pointer to the object that will be cleaned up.
499  * \param src Pointer to the object replacing it.
500  */
501 #define ao2_replace(dst, src) \
502  ao2_t_replace((dst), (src), NULL)
503 
504 #define ao2_t_replace(dst, src, tag) \
505  {\
506  typeof(dst) *__dst_ ## __LINE__ = &dst; \
507  typeof(src) __src_ ## __LINE__ = src; \
508  if (__src_ ## __LINE__ != *__dst_ ## __LINE__) { \
509  if (__src_ ## __LINE__) {\
510  ao2_t_ref(__src_ ## __LINE__, +1, (tag)); \
511  } \
512  if (*__dst_ ## __LINE__) {\
513  ao2_t_ref(*__dst_ ## __LINE__, -1, (tag)); \
514  } \
515  *__dst_ ## __LINE__ = __src_ ## __LINE__; \
516  } \
517  }
518 
519 /*! @} */
520 
521 /*! \brief ao2_weakproxy
522  *
523  * @{
524  */
526 typedef void (*ao2_weakproxy_notification_cb)(void *weakproxy, void *data);
527 
528 /*! \brief This struct should be opaque, but it's size is needed. */
531 };
532 
533 /*! \brief Macro which must be used at the beginning of weakproxy capable objects.
534  *
535  * \note The primary purpose of user defined fields on weakproxy objects is to hold
536  * immutable container keys for the real object.
537  */
538 #define AO2_WEAKPROXY() struct ao2_weakproxy __weakproxy##__LINE__
539 
540 /*!
541  * \since 14.0.0
542  * \brief Allocate an ao2_weakproxy object
543  *
544  * \param data_size The sizeof() of the user-defined structure.
545  * \param destructor_fn The destructor function (can be NULL)
546  *
547  * \note "struct ao2_weakproxy" must be the first field of any object.
548  * This can be done by using AO2_WEAKPROXY to declare your structure.
549  */
550 #define ao2_weakproxy_alloc(data_size, destructor_fn) \
551  __ao2_weakproxy_alloc(data_size, destructor_fn, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
552 
553 #define ao2_t_weakproxy_alloc(data_size, destructor_fn, tag) \
554  __ao2_weakproxy_alloc(data_size, destructor_fn, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
555 
556 void *__ao2_weakproxy_alloc(size_t data_size, ao2_destructor_fn destructor_fn,
557  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
558 
559 /*!
560  * \since 14.0.0
561  * \brief Associate weakproxy with obj.
562  *
563  * \param weakproxy An object created by ao2_weakproxy_alloc.
564  * \param obj An ao2 object not created by ao2_weakproxy_alloc.
565  * \param flags OBJ_NOLOCK to avoid locking weakproxy.
566  *
567  * \retval 0 Success
568  * \retval -1 Failure
569  *
570  * \note obj must be newly created, this procedure is not thread safe
571  * if any other code can reach obj before this procedure ends.
572  *
573  * \note weakproxy may be previously existing, but must not currently
574  * have an object set.
575  *
576  * \note The only way to unset an object is for it to be destroyed.
577  * Any call to this function while an object is already set will fail.
578  */
579 #define ao2_weakproxy_set_object(weakproxy, obj, flags) \
580  __ao2_weakproxy_set_object(weakproxy, obj, flags, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
581 
582 #define ao2_t_weakproxy_set_object(weakproxy, obj, flags, tag) \
583  __ao2_weakproxy_set_object(weakproxy, obj, flags, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
584 
585 int __ao2_weakproxy_set_object(void *weakproxy, void *obj, int flags,
586  const char *tag, const char *file, int line, const char *func);
587 
588 /*!
589  * \since 14.0.0
590  * \brief Run ao2_t_ref on the object associated with weakproxy.
591  *
592  * \param weakproxy The weakproxy to read from.
593  * \param delta Value to add to the reference counter.
594  * \param flags OBJ_NOLOCK to avoid locking weakproxy.
595  *
596  * \retval -2 weakproxy is not a valid ao2_weakproxy.
597  * \retval -1 weakproxy has no associated object.
598  *
599  * \return The value of the reference counter before the operation.
600  */
601 #define ao2_weakproxy_ref_object(weakproxy, delta, flags) \
602  ao2_t_weakproxy_ref_object(weakproxy, delta, flags, NULL)
603 
604 #define ao2_t_weakproxy_ref_object(weakproxy, delta, flags, tag) \
605  __ao2_weakproxy_ref_object(weakproxy, delta, flags, \
606  tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
607 
608 int __ao2_weakproxy_ref_object(void *weakproxy, int delta, int flags,
609  const char *tag, const char *file, int line, const char *func);
610 
611 /*!
612  * \since 14.0.0
613  * \brief Get the object associated with weakproxy.
614  *
615  * \param weakproxy The weakproxy to read from.
616  * \param flags OBJ_NOLOCK to avoid locking weakproxy.
617  *
618  * \return A reference to the object previously set by ao2_weakproxy_set_object.
619  * \retval NULL Either no object was set or the previously set object has been freed.
620  */
621 #define ao2_weakproxy_get_object(weakproxy, flags) \
622  __ao2_weakproxy_get_object(weakproxy, flags, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
623 
624 #define ao2_t_weakproxy_get_object(weakproxy, flags, tag) \
625  __ao2_weakproxy_get_object(weakproxy, flags, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
626 
627 void *__ao2_weakproxy_get_object(void *weakproxy, int flags,
628  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
629 
630 /*!
631  * \since 14.0.0
632  * \brief Request notification when weakproxy points to NULL.
633  *
634  * \param weakproxy The weak object
635  * \param cb Procedure to call when no real object is associated
636  * \param data Passed to cb
637  * \param flags OBJ_NOLOCK to avoid locking weakproxy.
638  *
639  * \retval 0 Success
640  * \retval -1 Failure
641  *
642  * \note Callbacks are run in the reverse order of subscriptions.
643  *
644  * \note This procedure will allow the same cb / data pair to be added to
645  * the same weakproxy multiple times.
646  *
647  * \note It is the caller's responsibility to ensure that *data is valid
648  * until after cb() is run or ao2_weakproxy_unsubscribe is called.
649  *
650  * \note If the weakproxy currently points to NULL the callback will be run immediately,
651  * without being added to the subscriber list.
652  */
653 int ao2_weakproxy_subscribe(void *weakproxy, ao2_weakproxy_notification_cb cb, void *data, int flags);
654 
655 /*!
656  * \since 14.0.0
657  * \brief Remove notification of real object destruction.
658  *
659  * \param weakproxy The weak object
660  * \param cb Callback to remove from destroy notification list
661  * \param data Data pointer to match
662  * \param flags OBJ_NOLOCK to avoid locking weakproxy.
663  * OBJ_MULTIPLE to remove all copies of the same cb / data pair.
664  *
665  * \return The number of subscriptions removed.
666  * \retval 0 cb / data pair not found, nothing removed.
667  * \retval -1 Failure due to invalid parameters.
668  *
669  * \note Unless flags includes OBJ_MULTIPLE, this will only remove a single copy
670  * of the cb / data pair. If it was subscribed multiple times it must be
671  * unsubscribed as many times. The OBJ_MULTIPLE flag can be used to remove
672  * matching subscriptions.
673  *
674  * \note When it's time to run callbacks they are copied to a temporary list so the
675  * weakproxy can be unlocked before running. That means it's possible for
676  * this function to find nothing before the callback is run in another thread.
677  */
678 int ao2_weakproxy_unsubscribe(void *weakproxy, ao2_weakproxy_notification_cb cb, void *data, int flags);
679 
680 /*!
681  * \since 14.0.0
682  * \brief Get the weakproxy attached to obj
683  *
684  * \param obj The object to retrieve a weakproxy from
685  *
686  * \return The weakproxy object
687  */
688 #define ao2_get_weakproxy(obj) \
689  __ao2_get_weakproxy(obj, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
690 
691 #define ao2_t_get_weakproxy(obj, tag) \
692  __ao2_get_weakproxy(obj, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
693 
694 void *__ao2_get_weakproxy(void *obj,
695  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
696 /*! @} */
697 
698 
699 /*! \brief Which lock to request. */
701  /*! Request the mutex lock be acquired. */
703  /*! Request the read lock be acquired. */
705  /*! Request the write lock be acquired. */
707 };
708 
709 /*! \brief
710  * Lock an object.
711  *
712  * \param a A pointer to the object we want to lock.
713  * \param lock_how, file, func, line, var
714  * \return 0 on success, other values on error.
715  */
716 int __ao2_lock(void *a, enum ao2_lock_req lock_how, const char *file, const char *func, int line, const char *var);
717 #define ao2_lock(a) __ao2_lock(a, AO2_LOCK_REQ_MUTEX, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
718 #define ao2_rdlock(a) __ao2_lock(a, AO2_LOCK_REQ_RDLOCK, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
719 #define ao2_wrlock(a) __ao2_lock(a, AO2_LOCK_REQ_WRLOCK, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
720 
721 /*! \brief
722  * Unlock an object.
723  *
724  * \param a A pointer to the object we want unlock.
725  * \param file, func, line, var
726  * \return 0 on success, other values on error.
727  */
728 int __ao2_unlock(void *a, const char *file, const char *func, int line, const char *var);
729 #define ao2_unlock(a) __ao2_unlock(a, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
730 
731 /*! \brief
732  * Try locking-- (don't block if fail)
733  *
734  * \param a A pointer to the object we want to lock.
735  * \param lock_how, file, func, line, var
736  * \return 0 on success, other values on error.
737  */
738 int __ao2_trylock(void *a, enum ao2_lock_req lock_how, const char *file, const char *func, int line, const char *var);
739 #define ao2_trylock(a) __ao2_trylock(a, AO2_LOCK_REQ_MUTEX, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
740 #define ao2_tryrdlock(a) __ao2_trylock(a, AO2_LOCK_REQ_RDLOCK, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
741 #define ao2_trywrlock(a) __ao2_trylock(a, AO2_LOCK_REQ_WRLOCK, __FILE__, __PRETTY_FUNCTION__, __LINE__, #a)
742 
743 /*!
744  * \brief Return the mutex lock address of an object
745  *
746  * \param[in] obj A pointer to the object we want.
747  * \return the address of the mutex lock, else NULL.
748  *
749  * This function comes in handy mainly for debugging locking
750  * situations, where the locking trace code reports the
751  * lock address, this allows you to correlate against
752  * object address, to match objects to reported locks.
753  *
754  * \warning AO2 lock objects do not include tracking fields when
755  * DEBUG_THREADS is not enabled.
756  *
757  * \since 1.6.1
758  */
759 void *ao2_object_get_lockaddr(void *obj);
760 
761 
762 /*!
763  * \brief Increment reference count on an object and lock it
764  * \since 13.9.0
765  *
766  * \param[in] obj A pointer to the ao2 object
767  * \retval 0 The object is not an ao2 object or wasn't locked successfully
768  * \retval 1 The object's reference count was incremented and was locked
769  */
771 int ao2_ref_and_lock(void *obj),
772 {
773  ao2_ref(obj, +1);
774  if (ao2_lock(obj)) {
775  ao2_ref(obj, -1);
776  return 0;
777  }
778  return 1;
779 }
780 )
781 
782 /*!
783  * \brief Unlock an object and decrement its reference count
784  * \since 13.9.0
785  *
786  * \param[in] obj A pointer to the ao2 object
787  * \retval 0 The object is not an ao2 object or wasn't unlocked successfully
788  * \retval 1 The object was unlocked and it's reference count was decremented
789  */
791 int ao2_unlock_and_unref(void *obj),
792 {
793  if (ao2_unlock(obj)) {
794  return 0;
795  }
796  ao2_ref(obj, -1);
797 
798  return 1;
799 }
800 )
801 
802 /*! Global ao2 object holder structure. */
804  /*! Access lock to the held ao2 object. */
806  /*! Global ao2 object. */
807  void *obj;
808 };
809 
810 /*!
811  * \brief Define a global object holder to be used to hold an ao2 object, statically initialized.
812  * \since 11.0
813  *
814  * \param name This will be the name of the object holder.
815  *
816  * \details
817  * This macro creates a global object holder that can be used to
818  * hold an ao2 object accessible using the API. The structure is
819  * allocated and initialized to be empty.
820  *
821  * Example usage:
822  * \code
823  * static AO2_GLOBAL_OBJ_STATIC(global_cfg);
824  * \endcode
825  *
826  * This defines global_cfg, intended to hold an ao2 object
827  * accessible using an API.
828  */
829 #ifndef HAVE_PTHREAD_RWLOCK_INITIALIZER
830 #define AO2_GLOBAL_OBJ_STATIC(name) \
831  struct ao2_global_obj name; \
832  static void __attribute__((constructor)) __init_##name(void) \
833  { \
834  ast_rwlock_init(&name.lock); \
835  name.obj = NULL; \
836  } \
837  static void __attribute__((destructor)) __fini_##name(void) \
838  { \
839  if (name.obj) { \
840  ao2_ref(name.obj, -1); \
841  name.obj = NULL; \
842  } \
843  ast_rwlock_destroy(&name.lock); \
844  } \
845  struct __dummy_##name
846 #else
847 #define AO2_GLOBAL_OBJ_STATIC(name) \
848  struct ao2_global_obj name = { \
849  .lock = AST_RWLOCK_INIT_VALUE, \
850  }
851 #endif
852 
853 /*!
854  * \brief Release the ao2 object held in the global holder.
855  * \since 11.0
856  *
857  * \param holder Global ao2 object holder.
858  */
859 #define ao2_global_obj_release(holder) \
860  __ao2_global_obj_replace_unref(&holder, NULL, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
861 #define ao2_t_global_obj_release(holder, tag) \
862  __ao2_global_obj_replace_unref(&holder, NULL, (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
863 
864 /*!
865  * \brief Replace an ao2 object in the global holder.
866  * \since 11.0
867  *
868  * \param holder Global ao2 object holder.
869  * \param obj Object to put into the holder. Can be NULL.
870  *
871  * \note This function automatically increases the reference
872  * count to account for the reference that the global holder now
873  * holds to the object.
874  *
875  * \return Reference to previous global ao2 object stored.
876  * \retval NULL if no object available.
877  */
878 #define ao2_global_obj_replace(holder, obj) \
879  __ao2_global_obj_replace(&holder, (obj), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
880 
881 #define ao2_t_global_obj_replace(holder, obj, tag) \
882  __ao2_global_obj_replace(&holder, (obj), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
883 
884 void *__ao2_global_obj_replace(struct ao2_global_obj *holder, void *obj, const char *tag, const char *file, int line, const char *func, const char *name) attribute_warn_unused_result;
885 
886 /*!
887  * \brief Replace an ao2 object in the global holder, throwing away any old object.
888  * \since 11.0
889  *
890  * \param holder Global ao2 object holder.
891  * \param obj Object to put into the holder. Can be NULL.
892  *
893  * \note This function automatically increases the reference
894  * count to account for the reference that the global holder now
895  * holds to the object. It also decreases the reference count
896  * of any object being replaced.
897  *
898  * \retval 0 The global object was previously empty
899  * \retval 1 The global object was not previously empty
900  */
901 #define ao2_global_obj_replace_unref(holder, obj) \
902  __ao2_global_obj_replace_unref(&holder, (obj), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
903 
904 #define ao2_t_global_obj_replace_unref(holder, obj, tag) \
905  __ao2_global_obj_replace_unref(&holder, (obj), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
906 
907 int __ao2_global_obj_replace_unref(struct ao2_global_obj *holder, void *obj, const char *tag, const char *file, int line, const char *func, const char *name);
908 
909 /*!
910  * \brief Get a reference to the object stored in the global holder.
911  * \since 11.0
912  *
913  * \param holder Global ao2 object holder.
914  *
915  * \return Reference to current ao2 object stored in the holder.
916  * \retval NULL if no object available.
917  */
918 #define ao2_global_obj_ref(holder) \
919  __ao2_global_obj_ref(&holder, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
920 
921 #define ao2_t_global_obj_ref(holder, tag) \
922  __ao2_global_obj_ref(&holder, (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__, #holder)
923 
924 void *__ao2_global_obj_ref(struct ao2_global_obj *holder, const char *tag, const char *file, int line, const char *func, const char *name) attribute_warn_unused_result;
925 
926 
927 /*!
928  \page AstObj2_Containers AstObj2 Containers
929 
930 Containers are data structures meant to store several objects,
931 and perform various operations on them.
932 Internally, objects are stored in lists, hash tables or other
933 data structures depending on the needs.
934 
935 Operations on container include:
936 
937  - \b ao2_find(c, arg, flags)
938  returns zero or more elements matching a given criteria
939  (specified as arg). 'c' is the container pointer. Flags
940  can be:
941  OBJ_UNLINK - to remove the object, once found, from the container.
942  OBJ_NODATA - don't return the object if found (no ref count change)
943  OBJ_MULTIPLE - don't stop at first match
944  OBJ_SEARCH_OBJECT - if set, 'arg' is an object pointer, and a hash table
945  search will be done. If not, a traversal is done.
946  OBJ_SEARCH_KEY - if set, 'arg', is a search key item that is not an object.
947  Similar to OBJ_SEARCH_OBJECT and mutually exclusive.
948  OBJ_SEARCH_PARTIAL_KEY - if set, 'arg', is a partial search key item that is not an object.
949  Similar to OBJ_SEARCH_KEY and mutually exclusive.
950 
951  - \b ao2_callback(c, flags, fn, arg)
952  apply fn(obj, arg) to all objects in the container.
953  Similar to find. fn() can tell when to stop, and
954  do anything with the object including unlinking it.
955  - c is the container;
956  - flags can be
957  OBJ_UNLINK - to remove the object, once found, from the container.
958  OBJ_NODATA - don't return the object if found (no ref count change)
959  OBJ_MULTIPLE - don't stop at first match
960  OBJ_SEARCH_OBJECT - if set, 'arg' is an object pointer, and a hash table
961  search will be done. If not, a traversal is done through
962  all the hash table 'buckets'..
963  OBJ_SEARCH_KEY - if set, 'arg', is a search key item that is not an object.
964  Similar to OBJ_SEARCH_OBJECT and mutually exclusive.
965  OBJ_SEARCH_PARTIAL_KEY - if set, 'arg', is a partial search key item that is not an object.
966  Similar to OBJ_SEARCH_KEY and mutually exclusive.
967  - fn is a func that returns int, and takes 3 args:
968  (void *obj, void *arg, int flags);
969  obj is an object
970  arg is the same as arg passed into ao2_callback
971  flags is the same as flags passed into ao2_callback
972  fn returns:
973  0: no match, keep going
974  CMP_STOP: stop search, no match
975  CMP_MATCH: This object is matched.
976 
977  Note that the entire operation is run with the container
978  locked, so nobody else can change its content while we work on it.
979  However, we pay this with the fact that doing
980  anything blocking in the callback keeps the container
981  blocked.
982  The mechanism is very flexible because the callback function fn()
983  can do basically anything e.g. counting, deleting records, etc.
984  possibly using arg to store the results.
985 
986  - \b iterate on a container
987  this is done with the following sequence
988 
989 \code
990 
991  struct ao2_container *c = ... // our container
992  struct ao2_iterator i;
993  void *o;
994 
995  i = ao2_iterator_init(c, flags);
996 
997  while ((o = ao2_iterator_next(&i))) {
998  ... do something on o ...
999  ao2_ref(o, -1);
1000  }
1001 
1002  ao2_iterator_destroy(&i);
1003 \endcode
1004 
1005  The difference with the callback is that the control
1006  on how to iterate is left to us.
1007 
1008  - \b ao2_ref(c, -1)
1009  dropping a reference to a container destroys it, very simple!
1010 
1011 Containers are ao2 objects themselves, and this is why their
1012 implementation is simple too.
1013 
1014 Before declaring containers, we need to declare the types of the
1015 arguments passed to the constructor - in turn, this requires
1016 to define callback and hash functions and their arguments.
1017 
1018 - \ref AstObj2
1019 - \ref astobj2.h
1020  */
1021 
1022 /*! \brief
1023  * A callback function will return a combination of CMP_MATCH and CMP_STOP.
1024  * The latter will terminate the search in a container.
1025  */
1027  CMP_MATCH = 0x1, /*!< the object matches the request */
1028  CMP_STOP = 0x2, /*!< stop the search now */
1029 };
1030 
1031 /*!
1032  * \brief Flags passed to ao2_callback_fn(), ao2_hash_fn(), and ao2_sort_fn() to modify behaviour.
1033  */
1035  /*!
1036  * Unlink the object for which the callback function returned
1037  * CMP_MATCH.
1038  */
1039  OBJ_UNLINK = (1 << 0),
1040  /*!
1041  * On match, don't return the object hence do not increase its
1042  * refcount.
1043  */
1044  OBJ_NODATA = (1 << 1),
1045  /*!
1046  * Don't stop at the first match in ao2_callback() unless the
1047  * result of the callback function has the CMP_STOP bit set.
1048  */
1049  OBJ_MULTIPLE = (1 << 2),
1050  /*!
1051  * \brief Assume that the ao2_container is already locked.
1052  *
1053  * \note For ao2_containers that have mutexes, no locking will
1054  * be done.
1055  *
1056  * \note For ao2_containers that have RWLOCKs, the lock will be
1057  * promoted to write mode as needed. The lock will be returned
1058  * to the original locked state.
1059  *
1060  * \note Only use this flag if the ao2_container is manually
1061  * locked already.
1062  */
1063  OBJ_NOLOCK = (1 << 4),
1064 
1065  /*!
1066  * \brief Search option field mask.
1067  *
1068  * \todo Eventually OBJ_SEARCH_MASK will shrink to a two bit
1069  * field when the codebase is made to use the search field
1070  * values as a field instead of independent bits.
1071  */
1072  OBJ_SEARCH_MASK = (0x07 << 5),
1073  /*! \brief The arg parameter has no meaning to the astobj2 code. */
1074  OBJ_SEARCH_NONE = (0 << 5),
1075  /*!
1076  * \brief The arg parameter is an object of the same type.
1077  *
1078  * \details
1079  * The arg parameter is an object of the same type as the one
1080  * being searched for, so use the object's ao2_hash_fn and/or
1081  * ao2_sort_fn functions for optimized searching.
1082  *
1083  * \note The supplied ao2_callback_fn is called after the
1084  * container nodes have been filtered by the ao2_hash_fn and/or
1085  * ao2_sort_fn functions.
1086  */
1087  OBJ_SEARCH_OBJECT = (1 << 5),
1088  /*!
1089  * \brief The arg parameter is a search key, but is not an object.
1090  *
1091  * \details
1092  * This can be used when you want to be able to pass custom data
1093  * to the container's stored ao2_hash_fn, ao2_sort_fn, and
1094  * ao2_find ao2_callback_fn functions that is not a full object,
1095  * but perhaps just a string.
1096  *
1097  * \note The supplied ao2_callback_fn is called after the
1098  * container nodes have been filtered by the ao2_hash_fn and/or
1099  * ao2_sort_fn functions.
1100  */
1101  OBJ_SEARCH_KEY = (2 << 5),
1102  /*!
1103  * \brief The arg parameter is a partial search key similar to OBJ_SEARCH_KEY.
1104  *
1105  * \details
1106  * The partial key can be used by the ao2_sort_fn to guide the
1107  * search to find a contiguous subset of a sorted container.
1108  * For example, a sorted container holds: "A", "B", "Bert",
1109  * "Beth", "Earnie". Doing a partial key search with "B" will
1110  * find the sorted subset of all held objects starting with "B".
1111  *
1112  * \note The supplied ao2_callback_fn is called after the
1113  * container nodes have been filtered by the ao2_sort_fn
1114  * function.
1115  */
1117 
1118  /*! \brief Traverse order option field mask. */
1119  OBJ_ORDER_MASK = (0x03 << 8),
1120  /*! \brief Traverse in ascending order (First to last container object) */
1122  /*! \brief Traverse in descending order (Last to first container object) */
1124  /*!
1125  * \brief Traverse in pre-order (Node then children, for tree container)
1126  *
1127  * \note For non-tree containers, it is up to the container type
1128  * to make the best interpretation of the order. For list and
1129  * hash containers, this also means ascending order because a
1130  * binary tree can degenerate into a list.
1131  */
1132  OBJ_ORDER_PRE = (2 << 8),
1133  /*!
1134  * \brief Traverse in post-order (Children then node, for tree container)
1135  *
1136  * \note For non-tree containers, it is up to the container type
1137  * to make the best interpretation of the order. For list and
1138  * hash containers, this also means descending order because a
1139  * binary tree can degenerate into a list.
1140  */
1141  OBJ_ORDER_POST = (3 << 8),
1142 };
1143 
1144 /*
1145  * Deprecated backward compatible flag names.
1146  *
1147  * Note: OBJ_POINTER, OBJ_KEY, and OBJ_PARTIAL_KEY are mutually
1148  * exclusive.
1149  */
1150 #define OBJ_POINTER OBJ_SEARCH_OBJECT /*!< Deprecated name */
1151 #define OBJ_KEY OBJ_SEARCH_KEY /*!< Deprecated name */
1152 #define OBJ_PARTIAL_KEY OBJ_SEARCH_PARTIAL_KEY /*!< Deprecated name */
1153 
1154 /*!
1155  * \brief Options available when allocating an ao2 container object.
1156  *
1157  * \note Each option is open to some interpretation by the
1158  * container type as long as it makes sense with the option
1159  * name.
1160  */
1162  /*!
1163  * \brief Insert objects at the beginning of the container.
1164  * (Otherwise it is the opposite; insert at the end.)
1165  *
1166  * \note If an ao2_sort_fn is provided, the object is inserted
1167  * before any objects with duplicate keys.
1168  *
1169  * \note Hash containers insert the object in the computed hash
1170  * bucket in the indicated manner.
1171  */
1173 
1174  /*!
1175  * \brief The ao2 container objects with duplicate keys option field mask.
1176  */
1178  /*!
1179  * \brief Allow objects with duplicate keys in container.
1180  */
1182  /*!
1183  * \brief Reject objects with duplicate keys in container.
1184  *
1185  * \note The container must be sorted. i.e. have an
1186  * ao2_sort_fn.
1187  */
1189  /*!
1190  * \brief Reject duplicate objects in container.
1191  *
1192  * \details Don't link the same object into the container twice.
1193  * However, you can link a different object with the same key.
1194  *
1195  * \note The container must be sorted. i.e. have an
1196  * ao2_sort_fn.
1197  *
1198  * \note It is assumed that the objects are located where the
1199  * search key says they should be located.
1200  */
1202  /*!
1203  * \brief Replace objects with duplicate keys in container.
1204  *
1205  * \details The existing duplicate object is removed and the new
1206  * object takes the old object's place.
1207  *
1208  * \note The container must be sorted. i.e. have an
1209  * ao2_sort_fn.
1210  */
1212 };
1213 
1214 /*!
1215  * \brief Type of a generic callback function
1216  * \param obj pointer to the (user-defined part) of an object.
1217  * \param arg callback argument from ao2_callback()
1218  * \param flags flags from ao2_callback()
1219  * OBJ_SEARCH_OBJECT - if set, 'arg', is an object.
1220  * OBJ_SEARCH_KEY - if set, 'arg', is a search key item that is not an object.
1221  * OBJ_SEARCH_PARTIAL_KEY - if set, 'arg', is a partial search key item that is not an object.
1222  *
1223  * The return values are a combination of enum _cb_results.
1224  * Callback functions are used to search or manipulate objects in a container.
1225  */
1226 typedef int (ao2_callback_fn)(void *obj, void *arg, int flags);
1227 
1228 /*! \brief A common ao2_callback is one that matches by address. */
1229 int ao2_match_by_addr(void *obj, void *arg, int flags);
1230 
1231 /*!
1232  * \brief Type of a generic callback function
1233  * \param obj pointer to the (user-defined part) of an object.
1234  * \param arg callback argument from ao2_callback()
1235  * \param data arbitrary data from ao2_callback()
1236  * \param flags flags from ao2_callback()
1237  * OBJ_SEARCH_OBJECT - if set, 'arg', is an object.
1238  * OBJ_SEARCH_KEY - if set, 'arg', is a search key item that is not an object.
1239  * OBJ_SEARCH_PARTIAL_KEY - if set, 'arg', is a partial search key item that is not an object.
1240  *
1241  * The return values are a combination of enum _cb_results.
1242  * Callback functions are used to search or manipulate objects in a container.
1243  */
1244 typedef int (ao2_callback_data_fn)(void *obj, void *arg, void *data, int flags);
1245 
1246 /*!
1247  * Type of a generic function to generate a hash value from an object.
1248  *
1249  * \param obj pointer to the (user-defined part) of an object.
1250  * \param flags flags from ao2_callback()
1251  * OBJ_SEARCH_OBJECT - if set, 'obj', is an object.
1252  * OBJ_SEARCH_KEY - if set, 'obj', is a search key item that is not an object.
1253  *
1254  * \note This function must be idempotent.
1255  *
1256  * \return Computed hash value.
1257  */
1258 typedef int (ao2_hash_fn)(const void *obj, int flags);
1259 
1260 /*!
1261  * \brief Type of generic container sort function.
1262  *
1263  * \param obj_left pointer to the (user-defined part) of an object.
1264  * \param obj_right pointer to the (user-defined part) of an object.
1265  * \param flags flags from ao2_callback()
1266  * OBJ_SEARCH_OBJECT - if set, 'obj_right', is an object.
1267  * OBJ_SEARCH_KEY - if set, 'obj_right', is a search key item that is not an object.
1268  * OBJ_SEARCH_PARTIAL_KEY - if set, 'obj_right', is a partial search key item that is not an object.
1269  *
1270  * \note This function must be idempotent.
1271  *
1272  * \retval negtaive if obj_left < obj_right
1273  * \retval 0 if obj_left == obj_right
1274  * \retval positive if obj_left > obj_right
1275  */
1276 typedef int (ao2_sort_fn)(const void *obj_left, const void *obj_right, int flags);
1277 
1278 /*! \name Object Containers
1279  * Here start declarations of containers.
1280  *
1281  * @{
1282  */
1283 struct ao2_container;
1284 
1285 /*!
1286  * \brief Allocate and initialize a hash container with the desired number of buckets.
1287  *
1288  * \details
1289  * We allocate space for a struct astobj_container, struct container
1290  * and the buckets[] array.
1291  *
1292  * \param ao2_options Container ao2 object options (See enum ao2_alloc_opts)
1293  * \param container_options Container behaviour options (See enum ao2_container_opts)
1294  * \param n_buckets Number of buckets for hash
1295  * \param hash_fn Pointer to a function computing a hash value. (NULL if everyting goes in first bucket.)
1296  * \param sort_fn Pointer to a sort function. (NULL to not sort the buckets.)
1297  * \param cmp_fn Pointer to a compare function used by ao2_find. (NULL to match everything)
1298  *
1299  * \return A pointer to a struct container.
1300  *
1301  * \note Destructor is set implicitly.
1302  */
1303 #define ao2_container_alloc_hash(ao2_options, container_options, n_buckets, hash_fn, sort_fn, cmp_fn) \
1304  __ao2_container_alloc_hash((ao2_options), (container_options), (n_buckets), (hash_fn), (sort_fn), (cmp_fn), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1305 
1306 #define ao2_t_container_alloc_hash(ao2_options, container_options, n_buckets, hash_fn, sort_fn, cmp_fn, tag) \
1307  __ao2_container_alloc_hash((ao2_options), (container_options), (n_buckets), (hash_fn), (sort_fn), (cmp_fn), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1308 
1309 struct ao2_container *__ao2_container_alloc_hash(unsigned int ao2_options,
1310  unsigned int container_options, unsigned int n_buckets, ao2_hash_fn *hash_fn,
1312  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
1313 
1314 /*!
1315  * \brief Allocate and initialize a list container.
1316  *
1317  * \param ao2_options Container ao2 object options (See enum ao2_alloc_opts)
1318  * \param container_options Container behaviour options (See enum ao2_container_opts)
1319  * \param sort_fn Pointer to a sort function. (NULL if list not sorted.)
1320  * \param cmp_fn Pointer to a compare function used by ao2_find. (NULL to match everything)
1321  *
1322  * \return A pointer to a struct container.
1323  *
1324  * \note Destructor is set implicitly.
1325  * \note Implemented as a degenerate hash table.
1326  */
1327 #define ao2_container_alloc_list(ao2_options, container_options, sort_fn, cmp_fn) \
1328  __ao2_container_alloc_list((ao2_options), (container_options), (sort_fn), (cmp_fn), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1329 
1330 #define ao2_t_container_alloc_list(ao2_options, container_options, sort_fn, cmp_fn, tag) \
1331  __ao2_container_alloc_list((ao2_options), (container_options), (sort_fn), (cmp_fn), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1332 
1333 struct ao2_container *__ao2_container_alloc_list(unsigned int ao2_options,
1334  unsigned int container_options, ao2_sort_fn *sort_fn, ao2_callback_fn *cmp_fn,
1335  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
1336 
1337 /*!
1338  * \brief Allocate and initialize a red-black tree container.
1339  *
1340  * \param ao2_options Container ao2 object options (See enum ao2_alloc_opts)
1341  * \param container_options Container behaviour options (See enum ao2_container_opts)
1342  * \param sort_fn Pointer to a sort function.
1343  * \param cmp_fn Pointer to a compare function used by ao2_find. (NULL to match everything)
1344  *
1345  * \return A pointer to a struct container.
1346  *
1347  * \note Destructor is set implicitly.
1348  */
1349 #define ao2_container_alloc_rbtree(ao2_options, container_options, sort_fn, cmp_fn) \
1350  __ao2_container_alloc_rbtree((ao2_options), (container_options), (sort_fn), (cmp_fn), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1351 
1352 #define ao2_t_container_alloc_rbtree(ao2_options, container_options, sort_fn, cmp_fn, tag) \
1353  __ao2_container_alloc_rbtree((ao2_options), (container_options), (sort_fn), (cmp_fn), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1354 
1355 struct ao2_container *__ao2_container_alloc_rbtree(unsigned int ao2_options, unsigned int container_options,
1357  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
1358 
1359 /*! \brief
1360  * Returns the number of elements in a container.
1361  */
1362 int ao2_container_count(struct ao2_container *c);
1363 
1364 /*!
1365  * \brief Copy all object references in the src container into the dest container.
1366  * \since 11.0
1367  *
1368  * \param dest Container to copy src object references into.
1369  * \param src Container to copy all object references from.
1370  * \param flags OBJ_NOLOCK if a lock is already held on both containers.
1371  * Otherwise, the src container is locked first.
1372  *
1373  * \pre The dest container must be empty. If the duplication fails, the
1374  * dest container will be returned empty.
1375  *
1376  * \note This can potentially be expensive because a malloc is
1377  * needed for every object in the src container.
1378  *
1379  * \retval 0 on success.
1380  * \retval -1 on error.
1381  */
1382 int ao2_container_dup(struct ao2_container *dest, struct ao2_container *src, enum search_flags flags);
1383 
1384 /*!
1385  * \brief Copy object references associated with src container weakproxies into the dest container.
1386  *
1387  * \param dest Container to copy src strong object references into.
1388  * \param src Container to copy all weak object references from.
1389  * \param flags OBJ_NOLOCK if a lock is already held on both containers.
1390  * Otherwise, the src container is locked first.
1391  *
1392  * \pre The dest container must be empty. If the duplication fails, the
1393  * dest container will be returned empty.
1394  *
1395  * \note This can potentially be expensive because a malloc is
1396  * needed for every object in the src container.
1397  *
1398  * \note Every object inside the container is locked by \ref ao2_weakproxy_get_object.
1399  * Any weakproxy in \p src with no associated object is ignored.
1400  *
1401  * \retval 0 on success.
1402  * \retval -1 on error.
1403  */
1404 int ao2_container_dup_weakproxy_objs(struct ao2_container *dest, struct ao2_container *src, enum search_flags flags);
1405 
1406 /*!
1407  * \brief Create a clone/copy of the given container.
1408  * \since 11.0
1409  *
1410  * \param orig Container to copy all object references from.
1411  * \param flags OBJ_NOLOCK if a lock is already held on the container.
1412  *
1413  * \note This can potentially be expensive because a malloc is
1414  * needed for every object in the orig container.
1415  *
1416  * \return Clone container on success.
1417  * \retval NULL on error.
1418  */
1419 #define ao2_container_clone(orig, flags) \
1420  __ao2_container_clone(orig, flags, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1421 
1422 #define ao2_t_container_clone(orig, flags, tag) \
1423  __ao2_container_clone(orig, flags, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1424 
1425 struct ao2_container *__ao2_container_clone(struct ao2_container *orig, enum search_flags flags,
1426  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
1427 
1428 /*!
1429  * \brief Print output.
1430  * \since 12.0.0
1431  *
1432  * \param where User data pointer needed to determine where to put output.
1433  * \param fmt printf type format string.
1434  */
1435 typedef void (ao2_prnt_fn)(void *where, const char *fmt, ...) __attribute__((format(printf, 2, 3)));
1436 
1437 /*!
1438  * \brief Print object key.
1439  * \since 12.0.0
1440  *
1441  * \param v_obj A pointer to the object we want the key printed.
1442  * \param where User data needed by prnt to determine where to put output.
1443  * \param prnt Print output callback function to use.
1444  */
1445 typedef void (ao2_prnt_obj_fn)(void *v_obj, void *where, ao2_prnt_fn *prnt);
1446 
1447 /*!
1448  * \brief Display contents of the specified container.
1449  * \since 12.0.0
1450  *
1451  * \param self Container to dump.
1452  * \param flags OBJ_NOLOCK if a lock is already held on the container.
1453  * \param name Container name. (NULL if anonymous)
1454  * \param where User data needed by prnt to determine where to put output.
1455  * \param prnt Print output callback function to use.
1456  * \param prnt_obj Callback function to print the given object's key. (NULL if not available)
1457  */
1458 void ao2_container_dump(struct ao2_container *self, enum search_flags flags, const char *name, void *where, ao2_prnt_fn *prnt, ao2_prnt_obj_fn *prnt_obj);
1459 
1460 /*!
1461  * \brief Display statistics of the specified container.
1462  * \since 12.0.0
1463  *
1464  * \param self Container to display statistics.
1465  * \param flags OBJ_NOLOCK if a lock is already held on the container.
1466  * \param name Container name. (NULL if anonymous)
1467  * \param where User data needed by prnt to determine where to put output.
1468  * \param prnt Print output callback function to use.
1469  */
1470 void ao2_container_stats(struct ao2_container *self, enum search_flags flags, const char *name, void *where, ao2_prnt_fn *prnt);
1471 
1472 /*!
1473  * \brief Perform an integrity check on the specified container.
1474  * \since 12.0.0
1475  *
1476  * \param self Container to check integrity.
1477  * \param flags OBJ_NOLOCK if a lock is already held on the container.
1478  *
1479  * \retval 0 on success.
1480  * \retval -1 on error.
1481  */
1482 int ao2_container_check(struct ao2_container *self, enum search_flags flags);
1483 
1484 /*!
1485  * \brief Register a container for CLI stats and integrity check.
1486  * \since 12.0.0
1487  *
1488  * \param name Name to register the container under.
1489  * \param self Container to register.
1490  * \param prnt_obj Callback function to print the given object's key. (NULL if not available)
1491  *
1492  * \retval 0 on success.
1493  * \retval -1 on error.
1494  */
1495 int ao2_container_register(const char *name, struct ao2_container *self, ao2_prnt_obj_fn *prnt_obj);
1496 
1497 /*!
1498  * \brief Unregister a container for CLI stats and integrity check.
1499  * \since 12.0.0
1500  *
1501  * \param name Name the container is registered under.
1502  */
1503 void ao2_container_unregister(const char *name);
1504 
1505 /*! @} */
1506 
1507 /*! \name Object Management
1508  * Here we have functions to manage objects.
1509  *
1510  * We can use the functions below on any kind of
1511  * object defined by the user.
1512  *
1513  * @{
1514  */
1515 
1516 /*!
1517  * \brief Add an object to a container.
1518  *
1519  * \param container The container to operate on.
1520  * \param obj The object to be added.
1521  *
1522  * \retval 0 on errors.
1523  * \retval 1 on success.
1524  *
1525  * This function inserts an object in a container according its key.
1526  *
1527  * \note Remember to set the key before calling this function.
1528  *
1529  * \note This function automatically increases the reference count to account
1530  * for the reference that the container now holds to the object.
1531  */
1532 #define ao2_link(container, obj) \
1533  __ao2_link((container), (obj), 0, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1534 #define ao2_t_link(container, obj, tag) \
1535  __ao2_link((container), (obj), 0, (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1536 
1537 /*!
1538  * \brief Add an object to a container.
1539  *
1540  * \param container The container to operate on.
1541  * \param obj The object to be added.
1542  * \param flags search_flags to control linking the object. (OBJ_NOLOCK)
1543  *
1544  * \retval 0 on errors.
1545  * \retval 1 on success.
1546  *
1547  * This function inserts an object in a container according its key.
1548  *
1549  * \note Remember to set the key before calling this function.
1550  *
1551  * \note This function automatically increases the reference count to account
1552  * for the reference that the container now holds to the object.
1553  */
1554 #define ao2_link_flags(container, obj, flags) \
1555  __ao2_link((container), (obj), (flags), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1556 #define ao2_t_link_flags(container, obj, flags, tag) \
1557  __ao2_link((container), (obj), (flags), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1558 
1559 int __ao2_link(struct ao2_container *c, void *obj_new, int flags,
1560  const char *tag, const char *file, int line, const char *func);
1561 
1562 /*!
1563  * \brief Remove an object from a container
1564  *
1565  * \param container The container to operate on.
1566  * \param obj The object to unlink.
1567  *
1568  * \retval NULL always
1569  *
1570  * \note The object requested to be unlinked must be valid. However, if it turns
1571  * out that it is not in the container, this function is still safe to
1572  * be called.
1573  *
1574  * \note If the object gets unlinked from the container, the container's
1575  * reference to the object will be automatically released. (The
1576  * refcount will be decremented).
1577  */
1578 #define ao2_unlink(container, obj) \
1579  __ao2_unlink((container), (obj), 0, NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1580 #define ao2_t_unlink(container, obj, tag) \
1581  __ao2_unlink((container), (obj), 0, (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1582 
1583 /*!
1584  * \brief Remove an object from a container
1585  *
1586  * \param container The container to operate on.
1587  * \param obj The object to unlink.
1588  * \param flags search_flags to control unlinking the object. (OBJ_NOLOCK)
1589  *
1590  * \retval NULL always
1591  *
1592  * \note The object requested to be unlinked must be valid. However, if it turns
1593  * out that it is not in the container, this function is still safe to
1594  * be called.
1595  *
1596  * \note If the object gets unlinked from the container, the container's
1597  * reference to the object will be automatically released. (The
1598  * refcount will be decremented).
1599  */
1600 #define ao2_unlink_flags(container, obj, flags) \
1601  __ao2_unlink((container), (obj), (flags), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1602 
1603 #define ao2_t_unlink_flags(container, obj, flags, tag) \
1604  __ao2_unlink((container), (obj), (flags), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1605 
1606 void *__ao2_unlink(struct ao2_container *c, void *obj, int flags,
1607  const char *tag, const char *file, int line, const char *func);
1608 
1609 /*! @} */
1610 
1611 
1612 /*! \brief
1613  * ao2_callback() is a generic function that applies cb_fn() to all objects
1614  * in a container, as described below.
1615  *
1616  * \param c A pointer to the container to operate on.
1617  * \param flags A set of flags specifying the operation to perform,
1618  * partially used by the container code, but also passed to
1619  * the callback.
1620  * - If OBJ_NODATA is set, ao2_callback will return NULL. No refcounts
1621  * of any of the traversed objects will be incremented.
1622  * On the converse, if it is NOT set (the default), the ref count
1623  * of the first matching object will be incremented and returned.
1624  * - If OBJ_MULTIPLE is set, the ref count of all matching objects will
1625  * be incremented in an iterator for a temporary container and returned.
1626  * - If OBJ_SEARCH_OBJECT is set, the traversed items will be restricted
1627  * to the objects in the bucket that the object key hashes to.
1628  * - If OBJ_SEARCH_KEY is set, the traversed items will be restricted
1629  * to the objects in the bucket that the object key hashes to.
1630  * \param cb_fn A function pointer, that will be called on all
1631  * objects, to see if they match. This function returns CMP_MATCH
1632  * if the object is matches the criteria; CMP_STOP if the traversal
1633  * should immediately stop, or both (via bitwise ORing), if you find a
1634  * match and want to end the traversal, and 0 if the object is not a match,
1635  * but the traversal should continue. This is the function that is applied
1636  * to each object traversed. Its arguments are:
1637  * (void *obj, void *arg, int flags), where:
1638  * obj is an object
1639  * arg is the same as arg passed into ao2_callback
1640  * flags is the same as flags passed into ao2_callback (flags are
1641  * also used by ao2_callback).
1642  * \param arg passed to the callback.
1643  *
1644  * \retval NULL on failure or no matching object found.
1645  *
1646  * \return object found if OBJ_MULTIPLE is not set in the flags
1647  * parameter.
1648  *
1649  * \return ao2_iterator pointer if OBJ_MULTIPLE is set in the
1650  * flags parameter. The iterator must be destroyed with
1651  * ao2_iterator_destroy() when the caller no longer needs it.
1652  *
1653  * If the function returns any objects, their refcount is incremented,
1654  * and the caller is in charge of decrementing them once done.
1655  *
1656  * Typically, ao2_callback() is used for two purposes:
1657  * - to perform some action (including removal from the container) on one
1658  * or more objects; in this case, cb_fn() can modify the object itself,
1659  * and to perform deletion should set CMP_MATCH on the matching objects,
1660  * and have OBJ_UNLINK set in flags.
1661  * - to look for a specific object in a container; in this case, cb_fn()
1662  * should not modify the object, but just return a combination of
1663  * CMP_MATCH and CMP_STOP on the desired object.
1664  * Other usages are also possible, of course.
1665  *
1666  * This function searches through a container and performs operations
1667  * on objects according on flags passed.
1668  * XXX describe better
1669  * The comparison is done calling the compare function set implicitly.
1670  * The arg pointer can be a pointer to an object or to a key,
1671  * we can say this looking at flags value.
1672  * If arg points to an object we will search for the object pointed
1673  * by this value, otherwise we search for a key value.
1674  * If the key is not unique we only find the first matching value.
1675  *
1676  * The use of flags argument is the follow:
1677  *
1678  * OBJ_UNLINK unlinks the object found
1679  * OBJ_NODATA on match, do not return an object
1680  * Callbacks use OBJ_NODATA as a default
1681  * functions such as find() do
1682  * OBJ_MULTIPLE return multiple matches
1683  * Default is no.
1684  * OBJ_SEARCH_OBJECT the pointer is to an object
1685  * OBJ_SEARCH_KEY the pointer is to a search key
1686  * OBJ_SEARCH_PARTIAL_KEY the pointer is to a partial search key
1687  *
1688  * \note When the returned object is no longer in use, ao2_ref() should
1689  * be used to free the additional reference possibly created by this function.
1690  *
1691  * @{
1692  */
1693 #define ao2_callback(c, flags, cb_fn, arg) \
1694  __ao2_callback((c), (flags), (cb_fn), (arg), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1695 
1696 #define ao2_t_callback(c, flags, cb_fn, arg, tag) \
1697  __ao2_callback((c), (flags), (cb_fn), (arg), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1698 
1699 void *__ao2_callback(struct ao2_container *c, enum search_flags flags,
1700  ao2_callback_fn *cb_fn, void *arg, const char *tag, const char *file, int line,
1701  const char *func);
1702 
1703 /*! @} */
1704 
1705 /*! \brief
1706  * ao2_callback_data() is a generic function that applies cb_fn() to all objects
1707  * in a container. It is functionally identical to ao2_callback() except that
1708  * instead of taking an ao2_callback_fn *, it takes an ao2_callback_data_fn *, and
1709  * allows the caller to pass in arbitrary data.
1710  *
1711  * This call would be used instead of ao2_callback() when the caller needs to pass
1712  * OBJ_SEARCH_OBJECT, OBJ_SEARCH_KEY, or OBJ_SEARCH_PARTIAL_KEY as part of the flags
1713  * argument (which in turn requires passing in a known pointer type for 'arg') and
1714  * also needs access to other non-global data to complete it's comparison or task.
1715  *
1716  * See the documentation for ao2_callback() for argument descriptions.
1717  *
1718  * \see ao2_callback()
1719  */
1720 
1721 #define ao2_t_callback_data(container, flags, cb_fn, arg, data, tag) \
1722  __ao2_callback_data((container), (flags), (cb_fn), (arg), (data), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1723 #define ao2_callback_data(container, flags, cb_fn, arg, data) \
1724  __ao2_callback_data((container), (flags), (cb_fn), (arg), (data), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1725 
1726 void *__ao2_callback_data(struct ao2_container *c, enum search_flags flags,
1727  ao2_callback_data_fn *cb_fn, void *arg, void *data, const char *tag, const char *file,
1728  int line, const char *func);
1729 
1730 /*! ao2_find() is a short hand for ao2_callback(c, flags, c->cmp_fn, arg)
1731  * XXX possibly change order of arguments ?
1732  */
1733 
1734 #define ao2_t_find(container, arg, flags, tag) \
1735  __ao2_find((container), (arg), (flags), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1736 #define ao2_find(container, arg, flags) \
1737  __ao2_find((container), (arg), (flags), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1738 
1739 void *__ao2_find(struct ao2_container *c, const void *arg, enum search_flags flags,
1740  const char *tag, const char *file, int line, const char *func);
1741 
1742 /*!
1743  * \brief Perform an ao2_find on a container with ao2_weakproxy objects, returning the real object.
1744  *
1745  * \note Only OBJ_SEARCH_* and OBJ_NOLOCK flags are supported by this function.
1746  * \see ao2_callback for description of arguments.
1747  */
1748 #define ao2_weakproxy_find(c, arg, flags, tag) \
1749  __ao2_weakproxy_find(c, arg, flags, tag, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1750 void *__ao2_weakproxy_find(struct ao2_container *c, const void *arg, enum search_flags flags,
1751  const char *tag, const char *file, int line, const char *func);
1752 
1753 /*! \brief
1754  *
1755  *
1756  * When we need to walk through a container, we use an
1757  * ao2_iterator to keep track of the current position.
1758  *
1759  * Because the navigation is typically done without holding the
1760  * lock on the container across the loop, objects can be
1761  * inserted or deleted or moved while we work. As a
1762  * consequence, there is no guarantee that we manage to touch
1763  * all the elements in the container, and it is possible that we
1764  * touch the same object multiple times.
1765  *
1766  * An iterator must be first initialized with
1767  * ao2_iterator_init(), then we can use o = ao2_iterator_next()
1768  * to move from one element to the next. Remember that the
1769  * object returned by ao2_iterator_next() has its refcount
1770  * incremented, and the reference must be explicitly released
1771  * when done with it.
1772  *
1773  * In addition, ao2_iterator_init() will hold a reference to the
1774  * container being iterated and the last container node found.
1775  * These objects will be unreffed when ao2_iterator_destroy() is
1776  * called to free up the resources used by the iterator (if
1777  * any).
1778  *
1779  * Example:
1780  *
1781  * \code
1782  *
1783  * struct ao2_container *c = ... // the container we want to iterate on
1784  * struct ao2_iterator i;
1785  * struct my_obj *o;
1786  *
1787  * i = ao2_iterator_init(c, flags);
1788  *
1789  * while ((o = ao2_iterator_next(&i))) {
1790  * ... do something on o ...
1791  * ao2_ref(o, -1);
1792  * }
1793  *
1794  * ao2_iterator_restart(&i);
1795  * while ((o = ao2_iterator_next(&i))) {
1796  * ... do something on o ...
1797  * ao2_ref(o, -1);
1798  * }
1799  *
1800  * ao2_iterator_destroy(&i);
1801  *
1802  * \endcode
1803  *
1804  */
1805 
1806 /*!
1807  * \brief The astobj2 iterator
1808  *
1809  * \note You are not supposed to know the internals of an iterator!
1810  * We would like the iterator to be opaque, unfortunately
1811  * its size needs to be known if we want to store it around
1812  * without too much trouble.
1813  * Anyways...
1814  * The iterator has a pointer to the container, and a flags
1815  * field specifying various things e.g. whether the container
1816  * should be locked or not while navigating on it.
1817  * The iterator "points" to the current container node.
1818  *
1819  * Details are in the implementation of ao2_iterator_next()
1820  */
1822  /*! The container (Has a reference) */
1823  struct ao2_container *c;
1824  /*! Last container node (Has a reference) */
1825  void *last_node;
1826  /*! Nonzero if the iteration has completed. */
1828  /*! operation flags (enum ao2_iterator_flags) */
1829  int flags;
1830 };
1831 
1832 /*! Flags that can be passed to ao2_iterator_init() to modify the behavior
1833  * of the iterator.
1834  */
1836  /*!
1837  * \brief Assume that the ao2_container is already locked.
1838  *
1839  * \note For ao2_containers that have mutexes, no locking will
1840  * be done.
1841  *
1842  * \note For ao2_containers that have RWLOCKs, the lock will be
1843  * promoted to write mode as needed. The lock will be returned
1844  * to the original locked state.
1845  *
1846  * \note Only use this flag if the ao2_container is manually
1847  * locked already. You should hold the lock until after
1848  * ao2_iterator_destroy(). If you must release the lock then
1849  * you must at least hold the lock whenever you call an
1850  * ao2_iterator_xxx function with this iterator.
1851  */
1853  /*!
1854  * Indicates that the iterator was dynamically allocated by
1855  * astobj2 API and should be freed by ao2_iterator_destroy().
1856  */
1858  /*!
1859  * Indicates that before the iterator returns an object from
1860  * the container being iterated, the object should be unlinked
1861  * from the container.
1862  */
1864  /*!
1865  * Iterate in descending order (Last to first container object)
1866  * (Otherwise ascending order)
1867  *
1868  * \note Other traversal orders such as pre-order and post-order
1869  * do not make sense because they require the container
1870  * structure to be static during the traversal. Iterators just
1871  * about guarantee that is not going to happen because the
1872  * container is allowed to change by other threads during the
1873  * iteration.
1874  */
1876 };
1877 
1878 /*!
1879  * \brief Create an iterator for a container
1880  *
1881  * \param c the container
1882  * \param flags one or more flags from ao2_iterator_flags.
1883  *
1884  * \return the constructed iterator
1885  *
1886  * \note This function does \b not take a pointer to an iterator;
1887  * rather, it returns an iterator structure that should be
1888  * assigned to (overwriting) an existing iterator structure
1889  * allocated on the stack or on the heap.
1890  *
1891  * This function will take a reference on the container being iterated.
1892  */
1894 
1895 /*!
1896  * \brief Destroy a container iterator
1897  *
1898  * \param iter the iterator to destroy
1899  *
1900  * This function will release the container reference held by the iterator
1901  * and any other resources it may be holding.
1902  */
1903 #if defined(TEST_FRAMEWORK)
1904 void ao2_iterator_destroy(struct ao2_iterator *iter) __attribute__((noinline));
1905 #else
1906 void ao2_iterator_destroy(struct ao2_iterator *iter);
1907 #endif /* defined(TEST_FRAMEWORK) */
1908 
1909 #define ao2_t_iterator_next(iter, tag) \
1910  __ao2_iterator_next((iter), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1911 #define ao2_iterator_next(iter) \
1912  __ao2_iterator_next((iter), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1913 
1914 void *__ao2_iterator_next(struct ao2_iterator *iter,
1915  const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result;
1916 
1917 /*!
1918  * \brief Restart an iteration.
1919  *
1920  * \param iter the iterator to restart
1921  *
1922  * \note A restart is not going to have any effect if the
1923  * iterator was created with the AO2_ITERATOR_UNLINK flag. Any
1924  * previous objects returned were removed from the container.
1925  */
1926 void ao2_iterator_restart(struct ao2_iterator *iter);
1927 
1928 /*! gcc __attribute__(cleanup()) functions
1929  * \note they must be able to handle NULL parameters because most of the
1930  * allocation/find functions can fail and we don't want to try to tear
1931  * down a NULL */
1932 void __ao2_cleanup(void *obj);
1933 void __ao2_cleanup_debug(void *obj, const char *tag, const char *file, int line, const char *function);
1934 #define ao2_cleanup(obj) __ao2_cleanup_debug((obj), NULL, __FILE__, __LINE__, __PRETTY_FUNCTION__)
1935 #define ao2_t_cleanup(obj, tag) __ao2_cleanup_debug((obj), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
1936 void ao2_iterator_cleanup(struct ao2_iterator *iter);
1937 
1938 /*!
1939  * \brief Get a count of the iterated container objects.
1940  *
1941  * \param iter the iterator to query
1942  *
1943  * \return The number of objects in the iterated container
1944  */
1945 int ao2_iterator_count(struct ao2_iterator *iter);
1946 
1947 /*!
1948  * \brief Creates a hash function for a structure field.
1949  * \param stype The structure type
1950  * \param field The string field in the structure to hash
1951  * \param hash_fn Function which hashes the field
1952  *
1953  * AO2_FIELD_HASH_FN(mystruct, myfield, ast_str_hash) will
1954  * produce a function named mystruct_hash_fn which hashes
1955  * mystruct->myfield with ast_str_hash.
1956  */
1957 #define AO2_FIELD_HASH_FN(stype, field, hash_fn) \
1958 static int stype ## _hash_fn(const void *obj, const int flags) \
1959 { \
1960  const struct stype *object = obj; \
1961  const char *key; \
1962  switch (flags & OBJ_SEARCH_MASK) { \
1963  case OBJ_SEARCH_KEY: \
1964  key = obj; \
1965  break; \
1966  case OBJ_SEARCH_OBJECT: \
1967  key = object->field; \
1968  break; \
1969  default: \
1970  ast_assert(0); \
1971  return 0; \
1972  } \
1973  return hash_fn(key); \
1974 }
1975 
1976 
1977 #define AO2_FIELD_TRANSFORM_CMP_FN(cmp) ((cmp) ? 0 : CMP_MATCH)
1978 #define AO2_FIELD_TRANSFORM_SORT_FN(cmp) (cmp)
1979 
1980 /*!
1981  * \internal
1982  *
1983  * \brief Creates a compare function for a structure string field.
1984  * \param stype The structure type
1985  * \param fn_suffix Function name suffix
1986  * \param field The string field in the structure to compare
1987  * \param key_cmp Key comparison function like strcmp
1988  * \param partial_key_cmp Partial key comparison function like strncmp
1989  * \param transform A macro that takes the cmp result as an argument
1990  * and transforms it to a return value.
1991  * \param argconst
1992  *
1993  * Do not use this macro directly, instead use macro's starting with
1994  * AST_STRING_FIELD.
1995  *
1996  * \warning The macro is an internal implementation detail, the API
1997  * may change at any time.
1998  */
1999 #define AO2_FIELD_CMP_FN(stype, fn_suffix, field, key_cmp, partial_key_cmp, transform, argconst) \
2000 static int stype ## fn_suffix(argconst void *obj, argconst void *arg, int flags) \
2001 { \
2002  const struct stype *object_left = obj, *object_right = arg; \
2003  const char *right_key = arg; \
2004  int cmp; \
2005  switch (flags & OBJ_SEARCH_MASK) { \
2006  case OBJ_SEARCH_OBJECT: \
2007  right_key = object_right->field; \
2008  case OBJ_SEARCH_KEY: \
2009  cmp = key_cmp(object_left->field, right_key); \
2010  break; \
2011  case OBJ_SEARCH_PARTIAL_KEY: \
2012  cmp = partial_key_cmp(object_left->field, right_key, strlen(right_key)); \
2013  break; \
2014  default: \
2015  cmp = 0; \
2016  break; \
2017  } \
2018  return transform(cmp); \
2019 }
2020 
2021 /*!
2022  * \brief Creates a hash function for a structure string field.
2023  * \param stype The structure type
2024  * \param field The string field in the structure to hash
2025  *
2026  * AO2_STRING_FIELD_HASH_FN(mystruct, myfield) will produce a function
2027  * named mystruct_hash_fn which hashes mystruct->myfield.
2028  *
2029  * AO2_STRING_FIELD_HASH_FN(mystruct, myfield) would do the same except
2030  * it uses the hash function which ignores case.
2031  */
2032 #define AO2_STRING_FIELD_HASH_FN(stype, field) \
2033  AO2_FIELD_HASH_FN(stype, field, ast_str_hash)
2034 #define AO2_STRING_FIELD_CASE_HASH_FN(stype, field) \
2035  AO2_FIELD_HASH_FN(stype, field, ast_str_case_hash)
2036 
2037 /*!
2038  * \brief Creates a compare function for a structure string field.
2039  * \param stype The structure type
2040  * \param field The string field in the structure to compare
2041  *
2042  * AO2_STRING_FIELD_CMP_FN(mystruct, myfield) will produce a function
2043  * named mystruct_cmp_fn which compares mystruct->myfield.
2044  *
2045  * AO2_STRING_FIELD_CASE_CMP_FN(mystruct, myfield) would do the same
2046  * except it performs case insensitive comparisons.
2047  */
2048 #define AO2_STRING_FIELD_CMP_FN(stype, field) \
2049  AO2_FIELD_CMP_FN(stype, _cmp_fn, field, strcmp, strncmp, AO2_FIELD_TRANSFORM_CMP_FN,)
2050 #define AO2_STRING_FIELD_CASE_CMP_FN(stype, field) \
2051  AO2_FIELD_CMP_FN(stype, _cmp_fn, field, strcasecmp, strncasecmp, AO2_FIELD_TRANSFORM_CMP_FN,)
2052 
2053 /*!
2054  * \brief Creates a sort function for a structure string field.
2055  * \param stype The structure type
2056  * \param field The string field in the structure to compare
2057  *
2058  * AO2_STRING_FIELD_SORT_FN(mystruct, myfield) will produce a function
2059  * named mystruct_sort_fn which compares mystruct->myfield.
2060  *
2061  * AO2_STRING_FIELD_CASE_SORT_FN(mystruct, myfield) would do the same
2062  * except it performs case insensitive comparisons.
2063  */
2064 #define AO2_STRING_FIELD_SORT_FN(stype, field) \
2065  AO2_FIELD_CMP_FN(stype, _sort_fn, field, strcmp, strncmp, AO2_FIELD_TRANSFORM_SORT_FN, const)
2066 #define AO2_STRING_FIELD_CASE_SORT_FN(stype, field) \
2067  AO2_FIELD_CMP_FN(stype, _sort_fn, field, strcasecmp, strncasecmp, AO2_FIELD_TRANSFORM_SORT_FN, const)
2068 
2069 #endif /* _ASTERISK_ASTOBJ2_H */
#define var
Definition: ast_expr2f.c:614
int ao2_container_dup(struct ao2_container *dest, struct ao2_container *src, enum search_flags flags)
Copy all object references in the src container into the dest container.
void() ao2_prnt_obj_fn(void *v_obj, void *where, ao2_prnt_fn *prnt)
Print object key.
Definition: astobj2.h:1445
int ao2_weakproxy_unsubscribe(void *weakproxy, ao2_weakproxy_notification_cb cb, void *data, int flags)
Remove notification of real object destruction.
Definition: astobj2.c:973
int ao2_weakproxy_subscribe(void *weakproxy, ao2_weakproxy_notification_cb cb, void *data, int flags)
Request notification when weakproxy points to NULL.
Definition: astobj2.c:934
unsigned int ao2_options_get(void *obj)
Retrieve the ao2 options used to create the object.
Definition: astobj2.c:781
_cb_results
A callback function will return a combination of CMP_MATCH and CMP_STOP. The latter will terminate th...
Definition: astobj2.h:1026
@ CMP_MATCH
Definition: astobj2.h:1027
@ CMP_STOP
Definition: astobj2.h:1028
void * __ao2_get_weakproxy(void *obj, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
Definition: astobj2.c:917
ao2_alloc_opts
Options available when allocating an ao2 object.
Definition: astobj2.h:361
@ AO2_ALLOC_OPT_LOCK_NOLOCK
Definition: astobj2.h:367
@ AO2_ALLOC_OPT_LOCK_OBJ
Definition: astobj2.h:376
@ AO2_ALLOC_OPT_LOCK_RWLOCK
Definition: astobj2.h:365
@ AO2_ALLOC_OPT_LOCK_MUTEX
Definition: astobj2.h:363
@ AO2_ALLOC_OPT_LOCK_MASK
Definition: astobj2.h:369
@ AO2_ALLOC_OPT_NO_REF_DEBUG
Definition: astobj2.h:378
void * __ao2_global_obj_replace(struct ao2_global_obj *holder, void *obj, const char *tag, const char *file, int line, const char *func, const char *name) attribute_warn_unused_result
void ao2_iterator_cleanup(struct ao2_iterator *iter)
void * __ao2_global_obj_ref(struct ao2_global_obj *holder, const char *tag, const char *file, int line, const char *func, const char *name) attribute_warn_unused_result
int __ao2_trylock(void *a, enum ao2_lock_req lock_how, const char *file, const char *func, int line, const char *var)
Try locking– (don't block if fail)
Definition: astobj2.c:342
int ao2_container_dup_weakproxy_objs(struct ao2_container *dest, struct ao2_container *src, enum search_flags flags)
Copy object references associated with src container weakproxies into the dest container.
int ao2_match_by_addr(void *obj, void *arg, int flags)
A common ao2_callback is one that matches by address.
int ao2_container_check(struct ao2_container *self, enum search_flags flags)
Perform an integrity check on the specified container.
struct ao2_container * __ao2_container_clone(struct ao2_container *orig, enum search_flags flags, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
void * __ao2_callback(struct ao2_container *c, enum search_flags flags, ao2_callback_fn *cb_fn, void *arg, const char *tag, const char *file, int line, const char *func)
void ao2_container_unregister(const char *name)
Unregister a container for CLI stats and integrity check.
void * __ao2_alloc_with_lockobj(size_t data_size, ao2_destructor_fn destructor_fn, void *lockobj, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
Definition: astobj2.c:774
ao2_lock_req
Which lock to request.
Definition: astobj2.h:700
@ AO2_LOCK_REQ_MUTEX
Definition: astobj2.h:702
@ AO2_LOCK_REQ_WRLOCK
Definition: astobj2.h:706
@ AO2_LOCK_REQ_RDLOCK
Definition: astobj2.h:704
void * ao2_object_get_lockaddr(void *obj)
Return the mutex lock address of an object.
Definition: astobj2.c:476
int ao2_container_count(struct ao2_container *c)
Returns the number of elements in a container.
void * __ao2_weakproxy_get_object(void *weakproxy, int flags, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
Definition: astobj2.c:889
void(* ao2_weakproxy_notification_cb)(void *weakproxy, void *data)
Definition: astobj2.h:526
void ao2_container_stats(struct ao2_container *self, enum search_flags flags, const char *name, void *where, ao2_prnt_fn *prnt)
Display statistics of the specified container.
int() ao2_callback_fn(void *obj, void *arg, int flags)
Type of a generic callback function.
Definition: astobj2.h:1226
ao2_iterator_flags
Definition: astobj2.h:1835
@ AO2_ITERATOR_UNLINK
Definition: astobj2.h:1863
@ AO2_ITERATOR_DONTLOCK
Assume that the ao2_container is already locked.
Definition: astobj2.h:1852
@ AO2_ITERATOR_MALLOCD
Definition: astobj2.h:1857
@ AO2_ITERATOR_DESCENDING
Definition: astobj2.h:1875
int __ao2_weakproxy_ref_object(void *weakproxy, int delta, int flags, const char *tag, const char *file, int line, const char *func)
Definition: astobj2.c:862
void(* ao2_destructor_fn)(void *vdoomed)
Typedef for an object destructor.
Definition: astobj2.h:358
void * __ao2_find(struct ao2_container *c, const void *arg, enum search_flags flags, const char *tag, const char *file, int line, const char *func)
int __ao2_link(struct ao2_container *c, void *obj_new, int flags, const char *tag, const char *file, int line, const char *func)
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) attribute_warn_unused_result
int ao2_ref_and_lock(void *obj)
Increment reference count on an object and lock it.
Definition: astobj2.h:780
struct ao2_iterator ao2_iterator_init(struct ao2_container *c, int flags) attribute_warn_unused_result
Create an iterator for a container.
int ao2_iterator_count(struct ao2_iterator *iter)
Get a count of the iterated container objects.
int() ao2_sort_fn(const void *obj_left, const void *obj_right, int flags)
Type of generic container sort function.
Definition: astobj2.h:1276
void ao2_iterator_restart(struct ao2_iterator *iter)
Restart an iteration.
#define ao2_unlock(a)
Definition: astobj2.h:729
int() ao2_hash_fn(const void *obj, int flags)
Definition: astobj2.h:1258
int __ao2_weakproxy_set_object(void *weakproxy, void *obj, int flags, const char *tag, const char *file, int line, const char *func)
Definition: astobj2.c:818
void * __ao2_weakproxy_alloc(size_t data_size, ao2_destructor_fn destructor_fn, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
Definition: astobj2.c:793
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) attribute_warn_unused_result
#define ao2_lock(a)
Definition: astobj2.h:717
#define ao2_ref(o, delta)
Reference/unreference an object and return the old refcount.
Definition: astobj2.h:459
int __ao2_global_obj_replace_unref(struct ao2_global_obj *holder, void *obj, const char *tag, const char *file, int line, const char *func, const char *name)
void __ao2_cleanup(void *obj)
Definition: astobj2.c:677
int ao2_container_register(const char *name, struct ao2_container *self, ao2_prnt_obj_fn *prnt_obj)
Register a container for CLI stats and integrity check.
void ao2_container_dump(struct ao2_container *self, enum search_flags flags, const char *name, void *where, ao2_prnt_fn *prnt, ao2_prnt_obj_fn *prnt_obj)
Display contents of the specified container.
void __ao2_cleanup_debug(void *obj, const char *tag, const char *file, int line, const char *function)
Definition: astobj2.c:670
void ao2_iterator_destroy(struct ao2_iterator *iter)
Destroy a container iterator.
void * __ao2_callback_data(struct ao2_container *c, enum search_flags flags, ao2_callback_data_fn *cb_fn, void *arg, void *data, const char *tag, const char *file, int line, const char *func)
int() ao2_callback_data_fn(void *obj, void *arg, void *data, int flags)
Type of a generic callback function.
Definition: astobj2.h:1244
struct ao2_container * __ao2_container_alloc_rbtree(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) attribute_warn_unused_result
int __ao2_ref(void *o, int delta, const char *tag, const char *file, int line, const char *func)
Definition: astobj2.c:498
void * __ao2_weakproxy_find(struct ao2_container *c, const void *arg, enum search_flags flags, const char *tag, const char *file, int line, const char *func)
search_flags
Flags passed to ao2_callback_fn(), ao2_hash_fn(), and ao2_sort_fn() to modify behaviour.
Definition: astobj2.h:1034
@ OBJ_ORDER_MASK
Traverse order option field mask.
Definition: astobj2.h:1119
@ OBJ_SEARCH_PARTIAL_KEY
The arg parameter is a partial search key similar to OBJ_SEARCH_KEY.
Definition: astobj2.h:1116
@ OBJ_ORDER_DESCENDING
Traverse in descending order (Last to first container object)
Definition: astobj2.h:1123
@ OBJ_SEARCH_OBJECT
The arg parameter is an object of the same type.
Definition: astobj2.h:1087
@ OBJ_ORDER_PRE
Traverse in pre-order (Node then children, for tree container)
Definition: astobj2.h:1132
@ OBJ_ORDER_ASCENDING
Traverse in ascending order (First to last container object)
Definition: astobj2.h:1121
@ OBJ_NOLOCK
Assume that the ao2_container is already locked.
Definition: astobj2.h:1063
@ OBJ_NODATA
Definition: astobj2.h:1044
@ OBJ_SEARCH_MASK
Search option field mask.
Definition: astobj2.h:1072
@ OBJ_MULTIPLE
Definition: astobj2.h:1049
@ OBJ_UNLINK
Definition: astobj2.h:1039
@ OBJ_ORDER_POST
Traverse in post-order (Children then node, for tree container)
Definition: astobj2.h:1141
@ OBJ_SEARCH_KEY
The arg parameter is a search key, but is not an object.
Definition: astobj2.h:1101
@ OBJ_SEARCH_NONE
The arg parameter has no meaning to the astobj2 code.
Definition: astobj2.h:1074
void * __ao2_iterator_next(struct ao2_iterator *iter, const char *tag, const char *file, int line, const char *func) attribute_warn_unused_result
int __ao2_unlock(void *a, const char *file, const char *func, int line, const char *var)
Unlock an object.
Definition: astobj2.c:288
int __ao2_lock(void *a, enum ao2_lock_req lock_how, const char *file, const char *func, int line, const char *var)
Lock an object.
Definition: astobj2.c:222
void * __ao2_unlink(struct ao2_container *c, void *obj, int flags, const char *tag, const char *file, int line, const char *func)
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:768
void() ao2_prnt_fn(void *where, const char *fmt,...)
Print output.
Definition: astobj2.h:1435
int ao2_unlock_and_unref(void *obj)
Unlock an object and decrement its reference count.
Definition: astobj2.h:800
ao2_container_opts
Options available when allocating an ao2 container object.
Definition: astobj2.h:1161
@ AO2_CONTAINER_ALLOC_OPT_DUPS_OBJ_REJECT
Reject duplicate objects in container.
Definition: astobj2.h:1201
@ AO2_CONTAINER_ALLOC_OPT_INSERT_BEGIN
Insert objects at the beginning of the container. (Otherwise it is the opposite; insert at the end....
Definition: astobj2.h:1172
@ AO2_CONTAINER_ALLOC_OPT_DUPS_ALLOW
Allow objects with duplicate keys in container.
Definition: astobj2.h:1181
@ AO2_CONTAINER_ALLOC_OPT_DUPS_REJECT
Reject objects with duplicate keys in container.
Definition: astobj2.h:1188
@ AO2_CONTAINER_ALLOC_OPT_DUPS_REPLACE
Replace objects with duplicate keys in container.
Definition: astobj2.h:1211
@ AO2_CONTAINER_ALLOC_OPT_DUPS_MASK
The ao2 container objects with duplicate keys option field mask.
Definition: astobj2.h:1177
static snd_pcm_format_t format
Definition: chan_alsa.c:106
#define attribute_warn_unused_result
Definition: compiler.h:71
static const char name[]
Definition: format_mp3.c:68
General Definitions for Asterisk top level program Included by asterisk.h to handle platform-specific...
Inlinable API function macro.
#define AST_INLINE_API(hdr, body)
Definition: inline_api.h:54
A set of macros to manage forward-linked lists.
Asterisk locking-related definitions:
AST_LIST_HEAD_NOLOCK(contactliststruct, contact)
Generic container type.
ao2_callback_fn * cmp_fn
void * obj
Definition: astobj2.h:807
ast_rwlock_t lock
Definition: astobj2.h:805
When we need to walk through a container, we use an ao2_iterator to keep track of the current positio...
Definition: astobj2.h:1821
int complete
Definition: astobj2.h:1827
struct ao2_container * c
Definition: astobj2.h:1823
void * last_node
Definition: astobj2.h:1825
This struct should be opaque, but it's size is needed.
Definition: astobj2.h:529
struct ao2_weakproxy::@214 destroyed_cb
Structure for rwlock and tracking information.
Definition: lock.h:156
static struct test_options options
static struct test_val a
static struct test_val c