autoRestore.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_UTILITIES_AUTORESTORE_HPP
#define SHARE_UTILITIES_AUTORESTORE_HPP

#include "memory/allocation.hpp"

// A simplistic template providing a general save-restore pattern through a
// local auto/stack object (scope).
//
template<typename T> class AutoSaveRestore : public StackObj {
public:
  AutoSaveRestore(T &loc) : _loc(loc) {
    _value = loc;
  }
  ~AutoSaveRestore() {
    _loc = _value;
  }
private:
  T &_loc;
  T _value;
};

// A simplistic template providing a general modify-restore pattern through a
// local auto/stack object (scope).
//
template<typename T> class AutoModifyRestore : private AutoSaveRestore<T> {
public:
  AutoModifyRestore(T &loc, T value) : AutoSaveRestore<T>(loc) {
    loc = value;
  }
};

#endif // SHARE_UTILITIES_AUTORESTORE_HPP