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diff --git a/util/fbcompose/PluginManager.cc b/util/fbcompose/PluginManager.cc
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+/** PluginManager.cc file for the fluxbox compositor. */
+
+// Copyright (c) 2011 Gediminas Liktaras (gliktaras at gmail dot com)
+//
+// 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.
+
+
+#ifdef HAVE_CONFIG_H
+    #include "config.h"
+#endif  // HAVE_CONFIG_H
+
+#include "PluginManager.hh"
+
+#include "BasePlugin.hh"
+#include "BaseScreen.hh"
+#include "Exceptions.hh"
+#include "Logging.hh"
+#include "Utility.hh"
+
+#include <algorithm>
+#include <dlfcn.h>
+#include <sstream>
+
+using namespace FbCompositor;
+
+
+//--- CONSTRUCTORS AND DESTRUCTORS ---------------------------------------------
+
+// Costructor.
+PluginManager::PluginManager(PluginType plugin_type, const BaseScreen &screen,
+                             const FbTk::FbString user_plugin_dir) :
+    m_screen(screen) {
+
+    m_plugin_type = plugin_type;
+    m_user_plugin_dir = user_plugin_dir;
+}
+
+// Destructor.
+PluginManager::~PluginManager() {
+    for (size_t i = 0; i < m_plugin_objects.size(); i++) {
+        delete m_plugin_objects[i];
+    }
+
+    std::map<FbTk::FbString, PluginLibData>::iterator it = m_plugin_libs.begin();
+    while (it != m_plugin_libs.end()) {
+        unloadPlugin(it);
+        ++it;
+    }
+}
+
+
+//--- PLUGIN MANIPULATION ------------------------------------------------------
+
+// Create a plugin object, load the appropriate library if needed.
+void PluginManager::createPluginObject(FbTk::FbString name, std::vector<FbTk::FbString> args) {
+    if (m_plugin_libs.find(name) == m_plugin_libs.end()) {
+        loadPlugin(name);
+    }
+
+    CreatePluginFunction create_function = m_plugin_libs.find(name)->second.create_function;
+    BasePlugin *new_plugin_object = (*create_function)(m_screen, args);
+    m_plugin_objects.push_back(new_plugin_object);
+}
+
+
+//--- INTERNAL PLUGIN MANIPULATION ---------------------------------------------
+
+// Load a plugin.
+void PluginManager::loadPlugin(FbTk::FbString name) {
+    static union {
+        void *void_ptr;
+        PluginTypeFunction plugin_type_func;
+        CreatePluginFunction create_plugin_func;
+    } obj_union;
+
+    std::vector<FbTk::FbString> paths = buildPluginPaths(name);
+
+    // Get the handle to the plugin so object.
+    void *handle = NULL;
+    for (size_t i = 0; i < paths.size(); i++) {
+        handle = dlopen(paths[i].c_str(), RTLD_LAZY | RTLD_LOCAL);
+        if (handle) {
+            break;
+        }
+    }
+    if (!handle) {
+        std::stringstream ss;
+        ss << "Could not find/load plugin \"" << name << "\".";
+        throw PluginException(ss.str());
+    }
+
+    // Check for the correct plugin type.
+    obj_union.void_ptr = getLibraryObject(handle, "pluginType", name.c_str(), "type function");
+    PluginTypeFunction type_func = obj_union.plugin_type_func;
+
+    if ((*(type_func))() != m_plugin_type) {
+        std::stringstream ss;
+        ss << "Plugin \"" << name << "\" is of the wrong type.";
+        throw PluginException(ss.str());
+    }
+
+    // Get the plugin creation function.
+    obj_union.void_ptr = getLibraryObject(handle, "createPlugin", name.c_str(), "creation function");
+    CreatePluginFunction create_func = obj_union.create_plugin_func;
+
+    // Track the loaded plugin.
+    PluginLibData plugin_data = { handle, create_func };
+    m_plugin_libs.insert(make_pair(name, plugin_data));
+}
+
+// Unload a plugin.
+void PluginManager::unloadPlugin(FbTk::FbString name) {
+    std::map<FbTk::FbString, PluginLibData>::iterator it = m_plugin_libs.find(name);
+
+    if (it == m_plugin_libs.end()) {
+        std::stringstream ss;
+        ss << "Plugin \"" << name << "\" is not loaded (unloadPlugin).";
+        throw PluginException(ss.str());
+    } else {
+        unloadPlugin(it);
+    }
+}
+
+// Unload a plugin (actual worker function).
+void PluginManager::unloadPlugin(std::map<FbTk::FbString, PluginLibData>::iterator it) {
+    dlclose(it->second.handle);
+
+    it->second.handle = NULL;
+    it->second.create_function = NULL;
+}
+
+
+//--- CONVENIENCE FUNCTIONS ----------------------------------------------------
+
+// Build a vector of search paths for a given plugin.
+std::vector<FbTk::FbString> PluginManager::buildPluginPaths(const FbTk::FbString &name) {
+    std::stringstream ss;
+    std::vector<FbTk::FbString> paths;
+
+    FbTk::FbString type_dir = "";
+    if (m_plugin_type == Plugin_OpenGL) {
+        type_dir = "opengl/";
+    } else if (m_plugin_type == Plugin_XRender) {
+        type_dir = "xrender/";
+    }
+
+    ss << "./plugins/" << type_dir << name << "/.libs/" << name << ".so";
+    paths.push_back(ss.str());
+    ss.str("");
+
+    ss << m_user_plugin_dir << type_dir << name << ".so";
+    paths.push_back(ss.str());
+    ss.str("");
+
+#ifdef FBCOMPOSE_PATH
+    ss << FBCOMPOSE_PATH << "/plugins/" << type_dir << name << ".so";
+    paths.push_back(ss.str());
+    ss.str("");
+#endif
+
+    paths.push_back(name);
+
+    return paths;
+}
+
+// Returns some object from the given library handle.
+void *PluginManager::getLibraryObject(void *handle, const char *object_name, const char *plugin_name,
+                                      const char *verbose_object_name) {
+    dlerror();
+    void *raw_object = dlsym(handle, object_name);
+    const char *error = dlerror();
+
+    if (error) {
+        dlclose(handle);
+        std::stringstream ss;
+        ss << "Error in loading " << verbose_object_name << " for \"" << plugin_name << "\" plugin: " << error;
+        throw PluginException(ss.str());
+    } else {
+        return raw_object;
+    }
+}