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
87
88
89
|
/*
* Copyright (C) 2015 Max Kellermann <max@duempel.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SCOPE_EXIT_HXX
#define SCOPE_EXIT_HXX
#include "Compiler.h"
#include <utility>
/**
* Internal class. Do not use directly.
*/
template<typename F>
class ScopeExitGuard : F {
bool enabled = true;
public:
explicit ScopeExitGuard(F &&f):F(std::forward<F>(f)) {}
ScopeExitGuard(ScopeExitGuard &&src)
:F(std::move(src)) {
src.enabled = false;
}
~ScopeExitGuard() {
if (enabled)
F::operator()();
}
ScopeExitGuard(const ScopeExitGuard &) = delete;
ScopeExitGuard &operator=(const ScopeExitGuard &) = delete;
};
/**
* Internal class. Do not use directly.
*/
struct ScopeExitTag {
/* this operator is a trick so we don't need to close
parantheses at the end of the expression AtScopeExit()
call */
template<typename F>
ScopeExitGuard<F> operator+(F &&f) {
return ScopeExitGuard<F>(std::forward<F>(f));
}
};
#define ScopeExitCat(a, b) a ## b
#define ScopeExitName(line) ScopeExitCat(at_scope_exit_, line)
/**
* Call the block after this macro at the end of the current scope.
* Parameters are lambda captures.
*
* This is exception-safe, however the given code block must not throw
* exceptions.
*
* This attempts to be a better boost/scope_exit.hpp, without all of
* Boost's compile-time and runtime bloat.
*/
#define AtScopeExit(...) auto ScopeExitName(__LINE__) = ScopeExitTag() + [__VA_ARGS__]()
#endif
|
