| 1 | /* | 
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| 2 | * Copyright 2016 Google Inc. | 
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| 3 | * | 
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| 4 | * Use of this source code is governed by a BSD-style license that can be | 
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| 5 | * found in the LICENSE file. | 
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| 6 | */ | 
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| 7 |  | 
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| 8 | #ifndef SkScopeExit_DEFINED | 
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| 9 | #define SkScopeExit_DEFINED | 
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| 10 |  | 
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| 11 | #include "include/core/SkTypes.h" | 
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| 12 | #include "include/private/SkMacros.h" | 
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| 13 |  | 
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| 14 | #include <functional> | 
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| 15 |  | 
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| 16 | /** SkScopeExit calls a std:::function<void()> in its destructor. */ | 
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| 17 | class SkScopeExit { | 
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| 18 | public: | 
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| 19 | SkScopeExit() = default; | 
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| 20 | SkScopeExit(std::function<void()> f) : fFn(std::move(f)) {} | 
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| 21 | SkScopeExit(SkScopeExit&& that) : fFn(std::move(that.fFn)) {} | 
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| 22 |  | 
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| 23 | ~SkScopeExit() { | 
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| 24 | if (fFn) { | 
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| 25 | fFn(); | 
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| 26 | } | 
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| 27 | } | 
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| 28 |  | 
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| 29 | void clear() { fFn = {}; } | 
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| 30 |  | 
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| 31 | SkScopeExit& operator=(SkScopeExit&& that) { | 
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| 32 | fFn = std::move(that.fFn); | 
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| 33 | return *this; | 
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| 34 | } | 
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| 35 |  | 
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| 36 | private: | 
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| 37 | std::function<void()> fFn; | 
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| 38 |  | 
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| 39 | SkScopeExit(           const SkScopeExit& ) = delete; | 
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| 40 | SkScopeExit& operator=(const SkScopeExit& ) = delete; | 
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| 41 | }; | 
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| 42 |  | 
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| 43 | /** | 
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| 44 | * SK_AT_SCOPE_EXIT(stmt) evaluates stmt when the current scope ends. | 
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| 45 | * | 
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| 46 | * E.g. | 
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| 47 | *    { | 
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| 48 | *        int x = 5; | 
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| 49 | *        { | 
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| 50 | *           SK_AT_SCOPE_EXIT(x--); | 
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| 51 | *           SkASSERT(x == 5); | 
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| 52 | *        } | 
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| 53 | *        SkASSERT(x == 4); | 
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| 54 | *    } | 
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| 55 | */ | 
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| 56 | #define SK_AT_SCOPE_EXIT(stmt)                              \ | 
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| 57 | SkScopeExit SK_MACRO_APPEND_LINE(at_scope_exit_)([&]() { stmt; }) | 
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| 58 |  | 
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| 59 | #endif  // SkScopeExit_DEFINED | 
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| 60 |  | 
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