VstBase: initial support for saving/restoring chunks

Some VST plugins save their state as chunks rather than parameters.
According code to save/restore those chunks has been taken from FST 1.9.
However restore currently is disabled as it mostly fails for whatever
reason.
(cherry picked from commit 0abd4aad70)

plugins/vst_base/remote_vst_plugin.cpp

@@ -38,6 +38,10 @@
 #include <pthread.h>
 #endif
 
+#ifdef LMMS_HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
 #ifdef LMMS_BUILD_LINUX
 
 #ifdef LMMS_HAVE_SCHED_H
@@ -184,6 +188,12 @@ public:
 	// post properties of specified parameter
 	void getParameterProperties( const int _idx );
 
+	// save settings chunk of plugin into file
+	void saveChunkToFile( const std::string & _file );
+
+	// restore settings chunk of plugin from file
+	void loadChunkFromFile( const std::string & _file, int _len );
+
 	// number of inputs
 	virtual int inputCount( void ) const
 	{
@@ -350,6 +360,16 @@ bool remoteVstPlugin::processMessage( const message & _m )
 			getParameterProperties( _m.getInt() );
 			break;
 
+		case IdSaveSettingsToFile:
+			saveChunkToFile( _m.getString() );
+			sendMessage( IdSaveSettingsToFile );
+			break;
+
+		case IdLoadSettingsFromFile:
+			loadChunkFromFile( _m.getString( 0 ), _m.getInt( 1 ) );
+			sendMessage( IdLoadSettingsFromFile );
+			break;
+
 		default:
 			return remotePluginClient::processMessage( _m );
 	}
@@ -800,6 +820,40 @@ void remoteVstPlugin::getParameterProperties( const int _idx )
 
 
 
+void remoteVstPlugin::saveChunkToFile( const std::string & _file )
+{
+	if( m_plugin->flags & 32 )
+	{
+		void * chunk = NULL;
+		int len = m_plugin->dispatcher( m_plugin, 23, 0, 0, &chunk, 0 );
+		if( len > 0 )
+		{
+			int fd = open( _file.c_str(), O_WRONLY );
+			write( fd, chunk, len );
+			close( fd );
+		}
+	}
+}
+
+
+
+
+void remoteVstPlugin::loadChunkFromFile( const std::string & _file, int _len )
+{
+	char * buf = new char[_len];
+
+	const int fd = open( _file.c_str(), O_RDONLY );
+	read( fd, buf, _len );
+	close( fd );
+
+	// doesn't work for various plugins for some reason :-(
+	// m_plugin->dispatcher( m_plugin, 24, 0, _len, buf, 0 );
+	delete[] buf;
+}
+
+
+
+
 void remoteVstPlugin::updateInOutCount( void )
 {
 	delete[] m_inputs;

plugins/vst_base/vst_plugin.cpp

@@ -28,6 +28,7 @@
 #include <QtCore/QDir>
 #include <QtCore/QFileInfo>
 #include <QtCore/QLocale>
+#include <QtCore/QTemporaryFile>
 #include <QtGui/QCloseEvent>
 #include <QtGui/QMdiArea>
 #include <QtGui/QMdiSubWindow>
@@ -250,6 +251,12 @@ void vstPlugin::loadSettings( const QDomElement & _this )
 		}
 		setParameterDump( dump );
 	}
+
+	if( _this.hasAttribute( "chunk" ) )
+	{
+		loadChunk( QByteArray::fromBase64(
+				_this.attribute( "chunk" ).toAscii() ) );
+	}
 }
 
 
@@ -268,6 +275,11 @@ void vstPlugin::saveSettings( QDomDocument & _doc, QDomElement & _this )
 	{
 		_this.setAttribute( it.key(), it.value() );
 	}
+	QByteArray chunk = saveChunk();
+	if( !chunk.isEmpty() )
+	{
+		_this.setAttribute( "chunk", QString( chunk.toBase64() ) );
+	}
 }
 
 
@@ -393,5 +405,44 @@ bool vstPlugin::processMessage( const message & _m )
 
 
 
+
+void vstPlugin::loadChunk( const QByteArray & _chunk )
+{
+	QTemporaryFile tf;
+	if( tf.open() )
+	{
+		tf.write( _chunk );
+		lock();
+		sendMessage( message( IdLoadSettingsFromFile ).
+				addString( QDir::toNativeSeparators(
+					tf.fileName() ).toStdString() ).
+				addInt( _chunk.size() ) );
+		waitForMessage( IdLoadSettingsFromFile );
+		unlock();
+	}
+}
+
+
+
+
+QByteArray vstPlugin::saveChunk( void )
+{
+	QByteArray a;
+	QTemporaryFile tf;
+	if( tf.open() )
+	{
+		lock();
+		sendMessage( message( IdSaveSettingsToFile ).
+				addString( QDir::toNativeSeparators(
+					tf.fileName() ).toStdString() ) );
+		waitForMessage( IdSaveSettingsToFile );
+		unlock();
+		a = tf.readAll();
+	}
+
+	return a;
+}
+
+
 #include "moc_vst_plugin.cxx"
 

plugins/vst_base/vst_plugin.h

@@ -1,7 +1,7 @@
 /*
  * vst_plugin.h - declaration of vstPlugin class
  *
- * Copyright (c) 2005-2008 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ * Copyright (c) 2005-2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
  * 
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
@@ -106,6 +106,9 @@ public slots:
 
 
 private:
+	void loadChunk( const QByteArray & _chunk );
+	QByteArray saveChunk( void );
+
 	QString m_plugin;
 	QWidget * m_pluginWidget;
 	int m_pluginWindowID;