Asterisk - The Open Source Telephony Project GIT-master-85241bd
named_locks.c
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1/*
2 * Asterisk -- An open source telephony toolkit.
3 *
4 * Copyright (C) 2016, Fairview 5 Engineering, LLC
5 *
6 * George Joseph <george.joseph@fairview5.com>
7 *
8 * See http://www.asterisk.org for more information about
9 * the Asterisk project. Please do not directly contact
10 * any of the maintainers of this project for assistance;
11 * the project provides a web site, mailing lists and IRC
12 * channels for your use.
13 *
14 * This program is free software, distributed under the terms of
15 * the GNU General Public License Version 2. See the LICENSE file
16 * at the top of the source tree.
17 */
18
19/*! \file
20 *
21 * \brief Named Locks
22 *
23 * \author George Joseph <george.joseph@fairview5.com>
24 */
25
26#include "asterisk.h"
27
28#include "asterisk/_private.h"
29#include "asterisk/astobj2.h"
31#include "asterisk/utils.h"
32
34#define NAMED_LOCKS_BUCKETS 101
35
38 char key[0];
39};
40
42};
43
46
47static void named_locks_shutdown(void)
48{
50}
51
53{
55 NAMED_LOCKS_BUCKETS, named_lock_proxy_hash_fn, NULL, named_lock_proxy_cmp_fn);
56 if (!named_locks) {
57 return -1;
58 }
59
61
62 return 0;
63}
64
65static void named_lock_proxy_cb(void *weakproxy, void *data)
66{
67 ao2_unlink(named_locks, weakproxy);
68}
69
70struct ast_named_lock *__ast_named_lock_get(const char *filename, int lineno, const char *func,
71 enum ast_named_lock_type lock_type, const char *keyspace, const char *key)
72{
73 struct named_lock_proxy *proxy;
74 struct ast_named_lock *lock;
75 int keylen = strlen(keyspace) + strlen(key) + 2;
76 char *concat_key = ast_alloca(keylen);
77
78 sprintf(concat_key, "%s-%s", keyspace, key); /* Safe */
79
82 __PRETTY_FUNCTION__, filename, lineno, func);
83 if (lock) {
86
87 return lock;
88 }
89
90 proxy = ao2_t_weakproxy_alloc(sizeof(*proxy) + keylen, NULL, concat_key);
91 if (!proxy) {
92 goto failure_cleanup;
93 }
94
95 lock = __ao2_alloc(sizeof(*lock) + keylen, NULL, lock_type, concat_key, filename, lineno, func);
96 if (!lock) {
97 goto failure_cleanup;
98 }
99
100 /* We have exclusive access to proxy and lock, no need for locking here. */
102 goto failure_cleanup;
103 }
104
106 goto failure_cleanup;
107 }
108
109 strcpy(proxy->key, concat_key); /* Safe */
112 ao2_t_ref(proxy, -1, "Release allocation reference");
113
114 return lock;
115
116failure_cleanup:
118
119 ao2_cleanup(proxy);
121
122 return NULL;
123}
Prototypes for public functions only of internal interest,.
ast_mutex_t lock
Definition: app_sla.c:331
Asterisk main include file. File version handling, generic pbx functions.
int ast_register_cleanup(void(*func)(void))
Register a function to be executed before Asterisk gracefully exits.
Definition: clicompat.c:19
#define ast_alloca(size)
call __builtin_alloca to ensure we get gcc builtin semantics
Definition: astmm.h:288
#define ao2_weakproxy_set_object(weakproxy, obj, flags)
Associate weakproxy with obj.
Definition: astobj2.h:579
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
#define ao2_t_ref(o, delta, tag)
Definition: astobj2.h:460
unsigned int ao2_options_get(void *obj)
Retrieve the ao2 options used to create the object.
Definition: astobj2.c:781
@ AO2_ALLOC_OPT_LOCK_MUTEX
Definition: astobj2.h:363
@ AO2_ALLOC_OPT_LOCK_MASK
Definition: astobj2.h:369
#define AO2_STRING_FIELD_CMP_FN(stype, field)
Creates a compare function for a structure string field.
Definition: astobj2.h:2048
#define ao2_cleanup(obj)
Definition: astobj2.h:1934
#define ao2_unlink(container, obj)
Remove an object from a container.
Definition: astobj2.h:1578
#define ao2_link_flags(container, obj, flags)
Add an object to a container.
Definition: astobj2.h:1554
#define ao2_t_weakproxy_alloc(data_size, destructor_fn, tag)
Definition: astobj2.h:553
#define ao2_unlock(a)
Definition: astobj2.h:729
#define ao2_lock(a)
Definition: astobj2.h:717
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)
#define AO2_STRING_FIELD_HASH_FN(stype, field)
Creates a hash function for a structure string field.
Definition: astobj2.h:2032
@ OBJ_NOLOCK
Assume that the ao2_container is already locked.
Definition: astobj2.h:1063
@ OBJ_SEARCH_KEY
The arg parameter is a search key, but is not an object.
Definition: astobj2.h:1101
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
#define ao2_container_alloc_hash(ao2_options, container_options, n_buckets, hash_fn, sort_fn, cmp_fn)
Allocate and initialize a hash container with the desired number of buckets.
Definition: astobj2.h:1303
struct ast_named_lock * __ast_named_lock_get(const char *filename, int lineno, const char *func, enum ast_named_lock_type lock_type, const char *keyspace, const char *key)
Definition: named_locks.c:70
ast_named_lock_type
Which type of lock to request.
Definition: named_locks.h:57
#define NAMED_LOCKS_BUCKETS
Definition: named_locks.c:34
static void named_lock_proxy_cb(void *weakproxy, void *data)
Definition: named_locks.c:65
static void named_locks_shutdown(void)
Definition: named_locks.c:47
int ast_named_locks_init(void)
Definition: named_locks.c:52
struct ao2_container * named_locks
Definition: named_locks.c:33
Named Locks.
#define NULL
Definition: resample.c:96
Generic container type.
Utility functions.
#define ast_assert(a)
Definition: utils.h:739