Subversion Repositories dloadsdl

/**
 * Example Application for Dynamic Loading of SDL
 * Copyright (C) 2010  Matthias -apoc- Hecker <apoc@sixserv.org>
 *
 * This program 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 <http://www.gnu.org/licenses/>.
 */
#include "DLLoader.h"

DLLoader::DLLoader()
{
    libhandle = NULL;
    load_proc_symbol_error = false;
}
// DLLoader::DLLoader(const DLLoader& orig) {}
DLLoader::~DLLoader() {}

bool DLLoader::Load(std::string library_filename)
{
    std::cout << "-------------- Load Library --------------" << std::endl;

    if (libhandle) {
        std::cout << "library already loaded" << std::endl;
        return true;
    }

    std::cout << "loading shared library: " << library_filename << std::endl;

#ifdef _WIN32
    libhandle = LoadLibrary(library_filename.c_str());
    if (libhandle == NULL) {
        std::cout << "error loading shared library" << std::endl;
        return false;
    }
#else
    libhandle = dlopen(library_filename.c_str(), RTLD_LAZY);
    if (libhandle == NULL) {
        std::cout << "error loading shared library: " << dlerror() << std::endl;
        return false;
    }
#endif

    std::cout << "loading library function symbols" << std::endl;
    LoadProcSymbols();

    if (load_proc_symbol_error) {
        std::cout << "error loading library function symbols" << std::endl;
        return false;
    }

    return true;
}

void DLLoader::Unload()
{
    std::cout << "------------- Unload Library -------------" << std::endl;

    UnloadProcSymbols();

    if (!libhandle) {
        std::cout << "library handle not loaded" << std::endl;
        return;
    }

#ifdef _WIN32
    FreeLibrary(libhandle);
#else
    if (dlclose(libhandle) != 0) {
        std::cout << "error closing library handle: " << dlerror() << std::endl;
        return;
    }
#endif

    std::cout << "successfully closed library handle" << std::endl;
    libhandle = NULL;
}

void DLLoader::LoadProcSymbols() {}
void DLLoader::UnloadProcSymbols() {}

void *DLLoader::LoadSymbol(const char *symbol_name)
{
    void *symbol = NULL;
#ifdef _WIN32
    symbol = (void *)GetProcAddress(libhandle, symbol_name);
#else
    symbol = dlsym(libhandle, symbol_name);
#endif

    if (symbol == NULL) {
        load_proc_symbol_error = true;
        std::cout << "error couldn't load library procedure symbol: " << symbol_name << std::endl;
    }

    return symbol;
}