PluginLoader.cpp

/***************************************************************************
 *                                                                         *
 *   (c) Art Tevs, MPI Informatik Saarbruecken                             *
 *       mailto: <tevs@mpi-sb.mpg.de>                                      *
 *                                                                         *
 *   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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/


//----------------------------------------------------------------------------------
// Includes
//----------------------------------------------------------------------------------
#include "PluginLoader.h"
#include "Log.h"

namespace nrEngine{
        
        //----------------------------------------------------------------------------------
        ScriptFunctionDec(loadPlugin, PluginLoader)
        {
                // check if the parameter count is valid
                if (args.size() <= 2){
                        NR_Log(Log::LOG_ENGINE, Log::LL_ERROR, "PluginLoader: loadPlugin(name, file) : wrong parameter count");
                        return ScriptResult(std::string("More parameters required! loadPlugin(name, file)"));
                }
                
                // try to load all the plugins given
                Engine::instance()->loadPlugin("", args[2], args[1]);

                // ok
                return ScriptResult();
        }
        
        //----------------------------------------------------------------------------------
        PluginLoader::PluginLoader() : IResourceLoader("PluginLoader")
        {
                initializeResourceLoader();
                
                // register some new functions by the scripting engine
                Engine::sScriptEngine()->add("loadPlugin", loadPlugin);
        }

        
        //----------------------------------------------------------------------------------
        PluginLoader::~PluginLoader()
        {
                // remove the functions provided to the scripting engine
                Engine::sScriptEngine()->del("loadPlugin");
        }
        
        //----------------------------------------------------------------------------------
        Result PluginLoader::initializeResourceLoader()
        {

                // fill out supported resource types;
                declareSupportedResourceType("Plugin");
                declareSupportedResourceType("nrPlugin");
                
                // we do only support dll files in windows version of our engine
#if NR_PLATFORM == NR_PLATFORM_WIN32
                declareSupportedFileType("dll");
                declareTypeMap("dll", "Plugin");
#elif NR_PLATFORM == NR_PLATFORM_LINUX
                declareSupportedFileType("so");
                declareTypeMap("so", "Plugin");
#endif
                return OK;
        }

        //----------------------------------------------------------------------------------
        std::string PluginLoader::getSuffix(const std::string& resType)
        {
#if NR_PLATFORM == NR_PLATFORM_WIN32
                return std::string("dll");
#elif NR_PLATFORM == NR_PLATFORM_LINUX
                return std::string("so");
#endif
        }

        //----------------------------------------------------------------------------------
        Result PluginLoader::loadResource(IResource* res, const std::string& fileName, PropertyList* param)
        {

                // check whenever we have a valid file name of the plugin
                if (fileName.length() <= 3){
                        NR_Log(Log::LOG_ENGINE, Log::LL_ERROR, "File name of the plugin is not valid %s. It must contain at least 3 characters.", fileName.c_str());
                        return RES_BAD_FILETYPE;
                }

                std::string name = fileName;
                
#if NR_PLATFORM == NR_PLATFORM_LINUX
                if (name.substr(name.length() - 3, 3) != ".so")
                {
                        // dlopen() does not add .so to the filename, like windows does for .dll
                        NR_Log(Log::LOG_ENGINE, Log::LL_WARNING, "\".so\" added to the plugin file name %s", name.c_str());
                        name += ".so";
                }
#elif NR_PLATFORM == NR_PLATFORM_WIN32
                if (name.substr(name.length() - 4, 4) == ".dll")
                {
                        // windows does automaticly add .dll to the file name, so we have to cut the name
                        name = name.substr(0, name.length() - 4);
                }               
#endif

                // set filename to the extended one
                std::list<std::string> flist;
                flist.push_back(name);
                res->setResourceFilename(flist);

                // call reloading method in resource, so it get loaded
                return res->reload(param);              
        }
        
        //----------------------------------------------------------------------------------
        IResource* PluginLoader::createResource(const std::string& resourceType, PropertyList* params)
        {       
                // create an plugin instance
                return new Plugin();
        }
        
        
        //----------------------------------------------------------------------------------
        IResource* PluginLoader::createEmptyResource(const std::string& resourceType)
        {
                // create an instance of empty plugin
                return new EmptyPlugin();       
        }
        
        
};

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