mirror of
https://github.com/klzgrad/naiveproxy.git
synced 2024-12-01 01:36:09 +03:00
44 lines
1.2 KiB
C++
44 lines
1.2 KiB
C++
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef BASE_AUTO_RESET_H_
|
|
#define BASE_AUTO_RESET_H_
|
|
|
|
#include <utility>
|
|
|
|
#include "base/macros.h"
|
|
|
|
// base::AutoReset<> is useful for setting a variable to a new value only within
|
|
// a particular scope. An base::AutoReset<> object resets a variable to its
|
|
// original value upon destruction, making it an alternative to writing
|
|
// "var = false;" or "var = old_val;" at all of a block's exit points.
|
|
//
|
|
// This should be obvious, but note that an base::AutoReset<> instance should
|
|
// have a shorter lifetime than its scoped_variable, to prevent invalid memory
|
|
// writes when the base::AutoReset<> object is destroyed.
|
|
|
|
namespace base {
|
|
|
|
template<typename T>
|
|
class AutoReset {
|
|
public:
|
|
AutoReset(T* scoped_variable, T new_value)
|
|
: scoped_variable_(scoped_variable),
|
|
original_value_(std::move(*scoped_variable)) {
|
|
*scoped_variable_ = std::move(new_value);
|
|
}
|
|
|
|
~AutoReset() { *scoped_variable_ = std::move(original_value_); }
|
|
|
|
private:
|
|
T* scoped_variable_;
|
|
T original_value_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(AutoReset);
|
|
};
|
|
|
|
} // namespace base
|
|
|
|
#endif // BASE_AUTO_RESET_H_
|