DynamicLoader.h

Go to the documentation of this file.

/*
 * SNode.C - A Slim Toolkit for Network Communication
 * Copyright (C) Volker Christian <me@vchrist.at>
 *               2020, 2021, 2022, 2023, 2024, 2025
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
 
/*
 * MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
 
#ifndef CORE_DYNAMICLOADER_H
#define CORE_DYNAMICLOADER_H
 
#ifndef DOXYGEN_SHOULD_SKIP_THIS
 
#include "core/system/dlfcn.h"
 
#include <cstddef>
#include <list>
#include <map>
#include <string>
 
#endif /* DOXYGEN_SHOULD_SKIP_THIS */
 
namespace core {
 
    class DynamicLoader {
    private:
        struct Library {
            std::string fileName;
            std::string canonicalFileName;
            void* handle = nullptr;
            std::size_t refCount = 0;
            bool closePending = false;
        };
 
    public:
        DynamicLoader() = delete;
        ~DynamicLoader() = delete;
 
        static void* dlOpen(const std::string& libFile, int flags = RTLD_LOCAL | RTLD_LAZY);
        static void dlCloseDelayed(void* handle);
        static int dlClose(void* handle);
        static const void* dlSym(void* handle, const std::string& symbol);
        static const char* dlError();
 
    private:
        static std::string canonicalizePath(const std::string& libFile);
        static int dlClose(Library& library);
 
        static int realExecDlClose(const Library& library);
        static void execDlCloseDeleyed();
        static void execDlCloseAll();
 
        static std::map<std::string, Library> dlOpenedLibraries;
        static std::map<void*, std::string> dlOpenedLibrariesByHandle;
        static std::list<std::string> closeQueue;
 
        friend class EventLoop;
        friend class EventMultiplexer;
    };
 
} // namespace core
 
#endif // CORE_DYNAMICLOADER_H