stealable.h

/*
 * Copyright © 2017-2023 Synthstrom Audible Limited
 *
 * This file is part of The Synthstrom Audible Deluge Firmware.
 *
 * The Synthstrom Audible Deluge Firmware is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program.
 * If not, see <https://www.gnu.org/licenses/>.
 */
 
#pragma once
 
#include "definitions_cxx.hpp"
#include <etl/intrusive_links.h>
 
// Please see explanation of memory allocation and "stealing" at the top of GeneralMemoryAllocator.h
 
struct Stealable : etl::bidirectional_link<0> {
    using link_type = etl::bidirectional_link<0>;
 
    Stealable() = default;
    virtual ~Stealable() {
        if (is_linked()) {
            unlink();
        }
    };
 
    virtual bool mayBeStolen(void* thingNotToStealFrom) = 0;
    virtual void steal(char const* errorCode) = 0; // You gotta also call the destructor after this.
    [[nodiscard]] virtual StealableQueue getAppropriateQueue() const = 0;
 
    uint32_t lastTraversalNo = 0xFFFFFFFF;

    [[nodiscard]]
    bool operator==(const Stealable& other) const {
        return this == &other;
    }
};