1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
/*************************************************************************/
/* safe_refcount.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#ifndef SAFE_REFCOUNT_H
#define SAFE_REFCOUNT_H
#include "os/mutex.h"
/* x86/x86_64 GCC */
#include "platform_config.h"
#include "typedefs.h"
uint32_t atomic_conditional_increment( register uint32_t * counter );
uint32_t atomic_decrement( register uint32_t * pw );
uint32_t atomic_increment( register uint32_t * pw );
struct SafeRefCount {
uint32_t count;
public:
// destroy() is called when weak_count_ drops to zero.
bool ref() { //true on success
return atomic_conditional_increment( &count ) != 0;
}
uint32_t refval() { //true on success
return atomic_conditional_increment( &count );
}
bool unref() { // true if must be disposed of
if( atomic_decrement ( &count ) == 0 ) {
return true;
}
return false;
}
uint32_t get() const { // nothrow
return count;
}
void init(uint32_t p_value=1) {
count=p_value;
}
};
#endif
|