library/cpp/messagebus/extra_ref.h


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

#pragma once 
 
#include <util/system/yassert.h> 
 
class TExtraRef { 
    TAtomic Holds; 
 
public: 
    TExtraRef()
        : Holds(false)
    {
    }
    ~TExtraRef() { 
        Y_VERIFY(!Holds);
    } 
 
    template <typename TThis> 
    void Retain(TThis* thiz) { 
        if (AtomicGet(Holds)) { 
            return; 
        } 
        if (AtomicCas(&Holds, 1, 0)) { 
            thiz->Ref(); 
        } 
    } 
 
    template <typename TThis> 
    void Release(TThis* thiz) { 
        if (!AtomicGet(Holds)) { 
            return; 
        } 
        if (AtomicCas(&Holds, 0, 1)) { 
            thiz->UnRef(); 
        } 
    } 
};