SynchronizedMap.h

/*
╔══════════════════════════════════════════════════════════════════════════════╗
║                       SIMPLY POWERFUL TOOLKIT (SPTK)                         ║
╟──────────────────────────────────────────────────────────────────────────────╢
║  copyright            © 1999-2022 Alexey Parshin. All rights reserved.       ║
║  email                alexeyp@gmail.com                                      ║
╚══════════════════════════════════════════════════════════════════════════════╝
┌──────────────────────────────────────────────────────────────────────────────┐
│   This library is free software; you can redistribute it and/or modify it    │
│   under the terms of the GNU Library General Public License as published by  │
│   the Free Software Foundation; either version 2 of the License, or (at your │
│   option) any later version.                                                 │
│                                                                              │
│   This library 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 Library   │
│   General Public License for more details.                                   │
│                                                                              │
│   You should have received a copy of the GNU Library General Public License  │
│   along with this library; if not, write to the Free Software Foundation,    │
│   Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.               │
│                                                                              │
│   Please report all bugs and problems to alexeyp@gmail.com.                  │
└──────────────────────────────────────────────────────────────────────────────┘
*/
 
#pragma once
 
#include <functional>
#include <map>
#include <sptk5/sptk.h>
 
namespace sptk {
 
template<class K, class T>
class SynchronizedMap
{
    mutable std::mutex m_sync;
 
    using Map = std::map<K, T>;
    Map m_map;
 
public:
    using CallbackFunction = std::function<bool(const K& key, T& item)>;
 
    virtual void insert(const K& key, const T& data)
    {
        std::scoped_lock lock(m_sync);
        m_map.emplace(key, data);
    }
 
    virtual bool get(const K& key, T& item, bool remove = false)
    {
        std::scoped_lock lock(m_sync);
        typename Map::iterator itor = m_map.find(key);
        if (itor == m_map.end())
        {
            return false;
        }
        item = itor->second;
        if (remove)
        {
            m_map.erase(itor);
        }
        return true;
    }
 
    virtual bool remove(const K& key)
    {
        std::scoped_lock lock(m_sync);
        typename Map::iterator itor = m_map.find(key);
        if (itor == m_map.end())
        {
            return false;
        }
        m_map.erase(itor);
        return true;
    }
 
    bool empty() const
    {
        std::scoped_lock lock(m_sync);
        return m_map.empty();
    }
 
    size_t size() const
    {
        std::scoped_lock lock(m_sync);
        return m_map.size();
    }
 
    void clear()
    {
        std::scoped_lock lock(m_sync);
        m_map.clear();
    }
 
    bool for_each(CallbackFunction callbackFunction)
    {
        std::scoped_lock lock(m_sync);
        for (auto itor: m_map)
        {
            if (!callbackFunction(itor.first, itor.second))
            {
                return false;
            }
        }
        return true;
    }
};
 
} // namespace sptk