1 /*------------------------------------------------------------------------------
2  *
3  * Copyright (c) 2011-2021, EURid vzw. All rights reserved.
4  * The YADIFA TM software product is provided under the BSD 3-clause license:
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  *
10  *        * Redistributions of source code must retain the above copyright
11  *          notice, this list of conditions and the following disclaimer.
12  *        * Redistributions in binary form must reproduce the above copyright
13  *          notice, this list of conditions and the following disclaimer in the
14  *          documentation and/or other materials provided with the distribution.
15  *        * Neither the name of EURid nor the names of its contributors may be
16  *          used to endorse or promote products derived from this software
17  *          without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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23  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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29  * POSSIBILITY OF SUCH DAMAGE.
30  *
31  *------------------------------------------------------------------------------
32  *
33  */
34 
35 /** @defgroup threading mutexes, ...
36  *  @ingroup dnscore
37  *  @brief
38  *
39  * @{
40  *
41  *----------------------------------------------------------------------------*/
42 #include "dnscore/dnscore-config.h"
43 #include <sys/types.h>
44 #include <unistd.h>
45 #include "dnscore/logger.h"
46 
47 #include "dnscore/rc.h"
48 
49 #define MODULE_MSG_HANDLE		g_system_logger
50 
51 void
rc_init_vtbl(rc_vtbl * vtbl,rc_free_method * free_callback,mutex_t * mtx)52 rc_init_vtbl(rc_vtbl *vtbl, rc_free_method *free_callback, mutex_t *mtx)
53 {
54     vtbl->free_callback = free_callback;
55     vtbl->mtx = mtx;
56 }
57 
58 void
rc_finalize_vtbl(rc_vtbl * vtbl)59 rc_finalize_vtbl(rc_vtbl *vtbl)
60 {
61     vtbl->free_callback = NULL;
62     vtbl->mtx = NULL;
63 }
64 
65 void
rc_set_internal(rc_s * rc,rc_vtbl * vtbl)66 rc_set_internal(rc_s *rc, rc_vtbl *vtbl)
67 {
68     rc->vtbl = vtbl;
69     rc->count = 0;
70 }
71 
72 void
rc_aquire_internal(rc_s * rc)73 rc_aquire_internal(rc_s *rc)
74 {
75     mutex_lock(rc->vtbl->mtx);
76     ++rc->count;
77     mutex_unlock(rc->vtbl->mtx);
78 }
79 
80 void
rc_release_internal(rc_s * rc,void * data)81 rc_release_internal(rc_s *rc, void *data)
82 {
83     mutex_lock(rc->vtbl->mtx);
84     if(--rc->count > 0)
85     {
86         mutex_unlock(rc->vtbl->mtx);
87     }
88     else
89     {
90         if(rc->count < 0)
91         {
92             // oopsie
93             log_err("negative RC count: %i rc=%p data=%p", rc->count, rc, data);
94             logger_flush(); // then abort()
95             abort();
96         }
97 
98         mutex_unlock(rc->vtbl->mtx);
99         rc->vtbl->free_callback(data);
100     }
101 }
102