f2992c79346c989eb7d31d2fad25665174aab57c
1 /*
2 * SysDB - src/include/core/object.h
3 * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
28 #ifndef SDB_CORE_OBJECT_H
29 #define SDB_CORE_OBJECT_H 1
31 #include <stdarg.h>
32 #include <stddef.h>
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
38 struct sdb_object;
39 typedef struct sdb_object sdb_object_t;
41 struct sdb_object {
42 int ref_cnt;
43 void (*destructor)(sdb_object_t *);
44 size_t size;
45 };
46 #define SDB_OBJECT_INIT { 1, NULL, 0 }
48 typedef struct {
49 sdb_object_t super;
50 void *data;
51 void (*destructor)(void *);
52 } sdb_object_wrapper_t;
54 #define SDB_OBJ(obj) ((sdb_object_t *)(obj))
55 #define SDB_OBJ_WRAPPER(obj) ((sdb_object_wrapper_t *)(obj))
57 /*
58 * sdb_object_create:
59 * Allocates a new sdb_object_t of the specified 'size'. The object will be
60 * initialized to zero and then passed on to the 'init' function (if
61 * specified). If specified, the 'destructor' will be called, when the
62 * reference count drops to zero and before freeing the memory allocated by
63 * the object itself.
64 *
65 * If the init function fails (returns a non-zero value), the object will be
66 * destructed and destroyed.
67 *
68 * The reference count of the new object will be 1.
69 *
70 * Returns:
71 * - the newly allocated object
72 * - NULL on error
73 */
74 sdb_object_t *
75 sdb_object_create(size_t size, int (*init)(sdb_object_t *, va_list),
76 void (*destructor)(sdb_object_t *), ...);
78 /*
79 * sdb_object_create_wrapper:
80 * Create a new sdb_object_t wrapping some arbitrary other object.
81 */
82 sdb_object_t *
83 sdb_object_create_wrapper(void *data, void (*destructor)(void *));
85 #define SDB_OBJECT_WRAPPER_STATIC(obj, destructor) \
86 { SDB_OBJECT_INIT, (obj), (destructor) }
88 /*
89 * sdb_object_deref:
90 * Dereference the object and free the allocated memory in case the ref-count
91 * drops to zero. In case a 'destructor' had been registered with the object,
92 * it will be called before freeing the memory.
93 */
94 void
95 sdb_object_deref(sdb_object_t *obj);
97 /*
98 * sdb_object_ref:
99 * Take ownership of the specified object, that is, increment the reference
100 * count by one.
101 */
102 void
103 sdb_object_ref(sdb_object_t *obj);
105 #ifdef __cplusplus
106 } /* extern "C" */
107 #endif
109 #endif /* ! SDB_CORE_OBJECT_H */
111 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */