plugin system: plugin management features added (loading and unloading)

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@1008 b45a01b8-16f6-495d-af2f-9b41ad6348cc

retroshare-gui/src/gui/PluginManager.cpp

@@ -0,0 +1,298 @@
+#include <QFile>
+#include <QDir>
+#include <QRegExp>
+
+#include <QDebug>
+
+#include <QWidget> //a strange thing: it compiles without this header, but 
+                  //then segfaults in some place
+
+#include "PluginManager.h"
+#include "plugins/PluginInterface.h"
+
+PluginManager::PluginManager()
+{
+
+}
+      
+void      
+PluginManager::defaultLoad( QString baseDir )
+{
+    QDir workDir(baseDir);
+/*  //=== find a file with last loaded plugins =====
+    QStringList lastLoaded;
+    QFile llFile( workDir.absolutePath()+"last_loaded.txt" )  ;
+    if ( llFile.open(QIODevice::ReadOnly) ) 
+    {
+       QString tmps;
+       QTextStream stream( &llFile ); // Set the stream to read from myFile
+       tmps = stream.readLine(); 
+
+       lastLoaded = tmps.split(";");
+       llFile.close();
+    }
+*/
+  //=== get current available plugins =====
+    QStringList currAvailable = workDir.entryList(QDir::Files);
+#if defined(Q_OS_WIN)    
+    QRegExp trx("*.dll") ;
+#else
+    QRegExp trx("*.so");
+#endif
+    trx.setPatternSyntax(QRegExp::Wildcard );
+
+    currAvailable.filter( trx );
+
+    qDebug() << "  " << "can load this plugins: " << currAvailable ;
+
+  //=== 
+    foreach(QString pluginFileName, currAvailable)
+    {
+       QString fullfn( workDir.absoluteFilePath( pluginFileName ) );
+       readPluginFromFile( fullfn);       
+    }//    foreach(QString pluginFileName, currAvailable)
+
+    qDebug() << "  " << "names are " << names;
+}
+
+//=============================================================================
+
+void
+PluginManager::readPluginFromFile(QString fullFileName)
+{
+    qDebug() << "  " << "processing file " << fullFileName;
+
+    QString errMess;
+    PluginInterface* plugin = loadPluginInterface(fullFileName, errMess) ;
+
+    QString plName = "Name undefined" ;
+    QWidget* plWidget = 0;
+    if (plugin)
+    {
+        plName = plugin->pluginName();
+        qDebug() << "  " << "got pluginName:"  << plName;
+/*               
+	 //=== load widget (only  if this plugin was loaded last time)  
+	   if ( lastLoaded.indexOf( pluginFileName) >= 0)
+	   {
+	       plWidget = plugin->pluginWidget() ;
+               if (plWidget)
+	       {
+                   // all was good, 
+                   qDebug() << "  " << "got widget..." ;
+                   emit loadDone( plName, plWidget);
+               }
+               else
+               {
+                   errMess = "Plugin Object can't create widget"  ;
+	       }
+           }
+*/
+       delete plugin;
+ 
+       names.append(plName);
+//       int tpi = (int)plWidget;
+       widgets.append(plWidget);
+       fileNames.append(fullFileName);
+
+       emit installComplete(plName);
+    }
+    else
+    {
+        emit installFailed( plName, errMess);
+    }
+}
+
+//=============================================================================
+
+PluginInterface* 
+PluginManager::loadPluginInterface(QString fileName, QString& errorMessage)
+{
+    errorMessage = "Default Error Message" ;
+    PluginInterface* plugin = 0 ;
+    QPluginLoader* plLoader = new QPluginLoader(fileName);
+
+    QObject *pluginObject = plLoader->instance();
+    if (pluginObject)
+    {
+        //qDebug() << "  " << "loaded..." ;
+	plugin = qobject_cast<PluginInterface*> (pluginObject) ;
+	   
+        if (plugin)
+        {
+            errorMessage = "No error" ;            
+        }
+        else
+	{
+	    errorMessage = "Cast to 'PluginInterface*' failed";         
+	}        
+    }
+    else
+    {
+       errorMessage = "Istance wasn't created: " + plLoader->errorString() ;
+    }
+
+
+    delete plLoader; // plugin instance will not be deleted with this action
+
+    return plugin;
+}
+
+/*
+plName = plugin->pluginName();
+//	       names.append(plddName);
+	       qDebug() << "  " << "got pluginName:"  << plName;
+               
+	     //=== load widget (only  if this plugin was loaded last time)  
+	       if ( lastLoaded.indexOf( pluginFileName) >= 0)
+	       {
+	           QWidget* pw = plugin->pluginWidget() ;
+                   if (pw)
+	           {
+		       // all was good, 
+		       qDebug() << "  " << "got widget..." ;
+		       plState = PS_Loaded;
+		       emit loadDone( plName, pw);
+		   }
+		   else
+		   {
+		      errMess = "Plugin Object can't create widget"  ;
+		      plState = PS_Failed ;
+		   }
+	       }
+	       else
+	       {
+		  plState = PS_Viewed ; //this is no error, all's normal
+	       }
+
+	   }
+	   
+
+//	       delete pluginObject;
+       }
+       else
+       {
+	  errMess = "Instance wasn't created: " + plLoader->errorString() ;
+       }
+
+
+}
+*/
+//=============================================================================
+
+PluginManager:: ~PluginManager()
+{
+   // delete all widgets
+   foreach(QWidget* wp, widgets)
+   {
+      if (wp)
+	 delete wp;
+   }   
+}
+
+//=============================================================================
+
+QStringList 
+PluginManager::availablePlugins()
+{
+    return names;
+}
+//=============================================================================
+    
+QStringList 
+PluginManager::loadedPlugins()
+{
+
+}
+     
+bool 
+PluginManager::isLoaded(QString pluginName)
+{
+}
+
+//=============================================================================
+
+void 
+PluginManager::loadPlugin(QString pluginName)
+{
+   qDebug() << "" << "PluginManager::loadPlugin called for" << pluginName;
+
+   int plIndex = names.indexOf( pluginName ) ;
+   if (plIndex >=0 )
+   {
+      QWidget* plWidget = widgets.at(plIndex);
+     //=== first, check if we loaded it before
+      if ( plWidget )
+      {
+	 emit loadFailed( pluginName,
+	                  "Error: plugin already loaded") ;
+	 return ;
+      }
+
+    //=== next, load it's interface
+      QString fn = fileNames.at(plIndex);
+      QString errMess;
+      PluginInterface* pliface = loadPluginInterface(fn, errMess);
+      if (pliface)
+      {
+       //=== now, get a widget
+	 plWidget = pliface->pluginWidget() ;
+         if (plWidget)
+         {
+           // all was good,
+             qDebug() << "  " << "got plg widget..." ;
+             emit loadDone( pluginName, plWidget );
+	     widgets[plIndex] = plWidget;
+	     return;
+         }
+	 else
+	 {
+	    emit loadFailed(pluginName, 
+		            "Error: instance can't create a widget");
+	    return;
+	 }
+      }
+      else
+      {
+          emit loadFailed( pluginName,
+	      	           tr("Error: failed to load interface for ") 
+			     + pluginName +"("+errMess+")");
+	  return;
+      }      
+   }
+   else
+   {
+       emit loadFailed( pluginName, 
+	                tr("Error: know nothing about plugin ") + pluginName );
+
+       qDebug() << "  " << "error: request to load " << pluginName
+	                << " failed (unknown file)" ;
+       return;
+   }
+
+}
+
+//=============================================================================
+
+void
+PluginManager::unloadPlugin(QString pluginName)
+{
+    qDebug() << "  " << "PluginManager::unloadPlugin called for" << pluginName;
+
+    int plIndex = names.indexOf( pluginName ) ;
+    if (plIndex >=0 )
+    {
+        QWidget* plWidget =  widgets.at(plIndex);
+	qDebug() << "in pm is " << (int)plWidget;
+	if ( plWidget )
+	{   //                    
+	    widgets[plIndex] = 0;//(QWidget*)0;
+	    qDebug() << "111" ;
+	    delete plWidget;
+	    qDebug() << "222" ;
+	}
+    }
+}
+
+//=============================================================================
+