1 /*
2 * Copyright (c) 2023 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15 #ifndef HDI_DEVICE_INTELL_VOICE_SCOPE_GUARD_H
16 #define HDI_DEVICE_INTELL_VOICE_SCOPE_GUARD_H
17
18 #include <utility>
19
20 namespace OHOS {
21 namespace IntelligentVoice {
22 namespace Utils {
23 template <typename Func>
24 class ScopeGuard {
25 public:
ScopeGuard(Func &&f)26 ScopeGuard(Func &&f) : func_(std::forward<Func>(f)), active_(true)
27 {
28 }
29
ScopeGuard(ScopeGuard &&rhs)30 ScopeGuard(ScopeGuard &&rhs) : func_(std::move(rhs.func)), active_(rhs.active_)
31 {
32 rhs.Disable();
33 }
34
~ScopeGuard()35 ~ScopeGuard()
36 {
37 if (active_) {
38 func_();
39 }
40 }
41
Disable()42 void Disable()
43 {
44 active_ = false;
45 }
46
Active() const47 bool Active() const
48 {
49 return active_;
50 }
51
EarlyExit()52 void EarlyExit()
53 {
54 if (active_) {
55 func_();
56 }
57 active_ = false;
58 }
59 private:
60 Func func_;
61 bool active_;
62 ScopeGuard() = delete;
63 ScopeGuard(const ScopeGuard &) = delete;
64 ScopeGuard &operator=(const ScopeGuard &) = delete;
65 ScopeGuard &operator=(ScopeGuard &&) = delete;
66 };
67
68 // tag dispatch
69 struct ScopeGuardOnExit {};
70
71 template <typename Func>
operator +(ScopeGuardOnExit, Func &&fn)72 inline ScopeGuard<Func> operator+(ScopeGuardOnExit, Func &&fn)
73 {
74 return ScopeGuard<Func>(std::forward<Func>(fn));
75 }
76 }
77 }
78 }
79
80 /*
81 * ScopeGuard ensure the specified function which is created by ON_SCOPE_EXIT is executed no matter how the current
82 * scope exit.
83 * when use ON_SCOPE_EXIT macro, the format is:
84 * ON_SCOPE_EXIT {
85 * your code
86 * };
87 */
88 #define ON_SCOPE_EXIT \
89 auto __onScopeGuardExit__ = OHOS::IntelligentVoice::Utils::ScopeGuardOnExit() + [&]()
90
91 #define CANCEL_SCOPE_EXIT \
92 (__onScopeGuardExit__.Disable())
93
94 #define EARLY_SCOPE_EXIT \
95 (__onScopeGuardExit__.EarlyExit())
96
97 #define ON_SCOPE_EXIT_WITH_NAME(variable_name) \
98 auto variable_name = OHOS::IntelligentVoice::Utils::ScopeGuardOnExit() + [&]()
99
100 #endif
101