ZeroTierOne/attic/core/ScopedPtr.hpp

/*
 * Copyright (c)2013-2021 ZeroTier, Inc.
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file in the project's root directory.
 *
 * Change Date: 2026-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2.0 of the Apache License.
 */
/****/

#ifndef ZT_SCOPEDPTR_HPP
#define ZT_SCOPEDPTR_HPP

#include "Constants.hpp"
#include "TriviallyCopyable.hpp"

namespace ZeroTier {

/**
 * Simple scoped pointer
 *
 * This is used in the core to avoid requiring C++11 and because auto_ptr is weird.
 */
template <typename T> class ScopedPtr : public TriviallyCopyable {
  public:
    explicit ZT_INLINE ScopedPtr(T *const p) noexcept : m_ptr(p) {}

    ZT_INLINE ~ScopedPtr() { delete m_ptr; }

    ZT_INLINE T *operator->() const noexcept { return m_ptr; }

    ZT_INLINE T &operator*() const noexcept { return *m_ptr; }

    ZT_INLINE T *ptr() const noexcept { return m_ptr; }

    ZT_INLINE void swap(const ScopedPtr &p) noexcept
    {
        T *const tmp = m_ptr;
        m_ptr        = p.m_ptr;
        p.m_ptr      = tmp;
    }

    explicit ZT_INLINE operator bool() const noexcept { return (m_ptr != (T *)0); }

    ZT_INLINE bool operator==(const ScopedPtr &p) const noexcept { return (m_ptr == p.m_ptr); }

    ZT_INLINE bool operator!=(const ScopedPtr &p) const noexcept { return (m_ptr != p.m_ptr); }

    ZT_INLINE bool operator==(T *const p) const noexcept { return (m_ptr == p); }

    ZT_INLINE bool operator!=(T *const p) const noexcept { return (m_ptr != p); }

  private:
    ZT_INLINE ScopedPtr() noexcept {}

    ZT_INLINE ScopedPtr(const ScopedPtr &p) noexcept : m_ptr(nullptr) {}

    ZT_INLINE ScopedPtr &operator=(const ScopedPtr &p) noexcept { return *this; }

    T *const m_ptr;
};

}   // namespace ZeroTier

namespace std {
template <typename T> ZT_INLINE void swap(ZeroTier::ScopedPtr<T> &a, ZeroTier::ScopedPtr<T> &b) noexcept { a.swap(b); }
}   // namespace std

#endif