pluginloader.cpp

//------------------------------------------------------------------------------
// pluginloader.cpp
//------------------------------------------------------------------------------
//
// 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.
//
// 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
// 02110-1301, USA.
//
//------------------------------------------------------------------------------
// Copyright (C) 2011 "Blzut3" <admin@maniacsvault.net>
//------------------------------------------------------------------------------
#include "pluginloader.h"

#include "log.h"
#include "configuration/doomseekerconfig.h"
#include "ini/inisection.h"
#include "ini/inivariable.h"
#include "plugins/engineplugin.h"
#include "serverapi/masterclient.h"
#include "strings.h"
#include <cassert>
#include <QDir>

#ifdef Q_OS_WIN32
        #include <windows.h>
        #define dlopen(a,b)     LoadLibrary(a)
        #define dlsym(a,b)      GetProcAddress(a, b)
        #define dlclose(a)      FreeLibrary(a)
        #define dlerror()       GetLastError()
        #ifdef _MSC_VER
                #pragma warning(disable: 4251)
        #endif
#else
        #include <dlfcn.h>
        #include <dirent.h>
#endif

DClass<PluginLoader::Plugin>
{
        public:
                EnginePlugin *info;
                QString file;
                #ifdef Q_OS_WIN32
                        HMODULE library;
                #else
                        void *library;
                #endif
};

DPointered(PluginLoader::Plugin)

PluginLoader::Plugin::Plugin(unsigned int type, QString file)
{
        d->file = file;
        // Load the library
        d->library = dlopen(d->file.toAscii().constData(), RTLD_NOW);

        if(d->library != NULL)
        {
                unsigned int (*doomSeekerABI)() = (unsigned int(*)()) (dlsym(d->library, "doomSeekerABI"));
                if(!doomSeekerABI || doomSeekerABI() != DOOMSEEKER_ABI_VERSION)
                {
                        // Unsupported version
                        unload();
                        return;
                }

                EnginePlugin *(*doomSeekerInit)() = (EnginePlugin *(*)()) (dlsym(d->library, "doomSeekerInit"));
                if(doomSeekerInit == NULL)
                { // This is not a valid plugin.
                        unload();
                        return;
                }

                d->info = doomSeekerInit();
                if(!info()->data()->valid)
                {
                        unload();
                        return;
                }

                gLog << QObject::tr("Loaded plugin: \"%1\"!").arg(info()->data()->name);
        }
        else
        {
                gLog << QObject::tr("Failed to open plugin: %1").arg(file);
                gLog << QString("Last error was: %1").arg(dlerror());
        }
}

PluginLoader::Plugin::~Plugin()
{
        unload();
}

void *PluginLoader::Plugin::function(const char* func) const
{
        return (void *) dlsym(d->library, func);
}

EnginePlugin *PluginLoader::Plugin::info() const
{
        return d->info;
}

void PluginLoader::Plugin::initConfig()
{
        if (isValid())
        {
                IniSection cfgSection = gConfig.iniSectionForPlugin(info()->data()->name);
                info()->setConfig(cfgSection);
        }
}

bool PluginLoader::Plugin::isValid() const
{
        return d->library != NULL;
}

void PluginLoader::Plugin::unload()
{
        if (d->library != NULL)
        {
                dlclose(d->library);
                d->library = NULL;
        }
}

DClass<PluginLoader>
{
        public:
                unsigned int type;
                QString pluginsDirectory;
                QList<PluginLoader::Plugin*> plugins;
};

DPointered(PluginLoader)

PluginLoader *PluginLoader::staticInstance = NULL;

PluginLoader::PluginLoader(unsigned int type, const QStringList &directories)
{
        d->type = type;
        foreach (const QString &dir, directories)
        {
                d->pluginsDirectory = dir;
                if (filesInDir())
                {
                        break;
                }
        }
        if (numPlugins() == 0) // No plugins?!
        {
                gLog << QObject::tr("Failed to locate plugins.");
        }
}

PluginLoader::~PluginLoader()
{
        qDeleteAll(d->plugins);
}

void PluginLoader::clearPlugins()
{
        qDeleteAll(d->plugins);
        d->plugins.clear();
}

void PluginLoader::deinit()
{
        if (staticInstance != NULL)
        {
                delete staticInstance;
                staticInstance = NULL;
        }
}

bool PluginLoader::filesInDir()
{
        gLog << QString("Attempting to load plugins from directory: %1").arg(d->pluginsDirectory);
        QDir dir(d->pluginsDirectory);
        if (!dir.exists())
        {
                return false;
        }
#ifdef Q_OS_WIN32
        QStringList windowsNamesFilter;
        windowsNamesFilter << "*.dll";
        dir.setNameFilters(windowsNamesFilter);
#endif
        foreach (const QString& entry, dir.entryList(QDir::Files))
        {
                QString pluginFilePath = Strings::combinePaths(d->pluginsDirectory, entry);
                Plugin *plugin = new Plugin(d->type, pluginFilePath);
                if (plugin->isValid())
                        d->plugins << plugin;
                else
                        delete plugin;
        }
        return numPlugins() != 0;
}

EnginePlugin *PluginLoader::info(int pluginIndex) const
{
        const Plugin* p = plugin(pluginIndex);
        if (p != NULL)
        {
                return p->info();
        }
        return NULL;
}

void PluginLoader::init(const QStringList &directories)
{
        if (staticInstance != NULL)
        {
                qDebug() << "Attempting to re-init PluginLoader";
                assert(false);
                return;
        }
        staticInstance = new PluginLoader(MAKEID('E', 'N', 'G', 'N'), directories);
}

void PluginLoader::initConfig()
{
        foreach (Plugin *plugin, d->plugins)
        {
                plugin->initConfig();
        }
}

PluginLoader *PluginLoader::instance()
{
        assert(staticInstance != NULL);
        return staticInstance;
}

const unsigned int PluginLoader::numPlugins() const
{
        return d->plugins.size();
}

const QList<PluginLoader::Plugin*> &PluginLoader::plugins() const
{
        return d->plugins;
}

const PluginLoader::Plugin* PluginLoader::plugin(unsigned int index) const
{
        return d->plugins[index];
}

int PluginLoader::pluginIndexFromName(const QString& name) const
{
        // Why the mangling?
        // Ever since version 0.8.1b there was a bug that removed all spacebars
        // from plugin names. This bug is fixed in a commit made on 2013-11-01,
        // but the fix breaks at least some parts of configuration for plugins
        // that have spacebars in their names. For example, all server
        // configurations for Chocolate Doom won't load anymore. To prevent that,
        // we need to treat spacebars as non-existent here. Simply put:
        // "Chocolate Doom" == "ChocolateDoom"
        QString mangledName = QString(name).replace(" ", "");
        for (int i = 0; i < d->plugins.size(); ++i)
        {
                QString mangledCandidate = QString(d->plugins[i]->info()->data()->name).replace(" ", "");
                if (mangledName.compare(mangledCandidate) == 0)
                {
                        return i;
                }
        }

        return -1;
}

void PluginLoader::resetPluginsDirectory(const QString& pluginsDirectory)
{
        d->pluginsDirectory = pluginsDirectory;
        clearPlugins();
        filesInDir();
}

const PluginLoader::Plugin* PluginLoader::operator[] (unsigned int index) const
{
        return d->plugins[index];
}