EnvelopeAndLfoParameters: moved global instances management into helper class

It's a bad style to manage global instances of an object in the object
itself. Therefore introduced a nested helper class which manages all
instances of EnvelopeAndLfoParameters globally. It is now responsible
for global reset/triggers of LFOs. In contrast to previous state, this
is now done thread-safe. Fixes crashes for example while importing
MIDI files.
(cherry picked from commit 5f6c42f19c)

include/EnvelopeAndLfoParameters.h

@@ -1,7 +1,7 @@
 /*
  * EnvelopeAndLfoParameters.h - class EnvelopeAndLfoParameters
  *
- * Copyright (c) 2004-2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ * Copyright (c) 2004-2010 Tobias Doerffel <tobydox/at/users.sourceforge.net>
  *
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
@@ -22,7 +22,6 @@
  *
  */
 
-
 #ifndef _ENVELOPE_AND_LFO_PARAMETERS_H
 #define _ENVELOPE_AND_LFO_PARAMETERS_H
 
@@ -35,11 +34,39 @@
 #include "lmms_basics.h"
 
 
-
 class EXPORT EnvelopeAndLfoParameters : public Model, public JournallingObject
 {
 	Q_OBJECT
 public:
+	class LfoInstances
+	{
+	public:
+		LfoInstances()
+		{
+		}
+
+		~LfoInstances()
+		{
+		}
+
+		inline bool isEmpty() const
+		{
+			return m_lfos.isEmpty();
+		}
+
+		void trigger();
+		void reset();
+
+		void add( EnvelopeAndLfoParameters * lfo );
+		void remove( EnvelopeAndLfoParameters * lfo );
+
+	private:
+		QMutex m_lfoListMutex;
+		typedef QList<EnvelopeAndLfoParameters *> LfoList;
+		LfoList m_lfos;
+
+	} ;
+
 	EnvelopeAndLfoParameters( float _value_for_zero_amount,
 							Model * _parent );
 	virtual ~EnvelopeAndLfoParameters();
@@ -49,8 +76,10 @@ public:
 		return ( ( _val < 0 ) ? -_val : _val ) * _val;
 	}
 
-	static void triggerLfo();
-	static void resetLfo();
+	static LfoInstances * instances()
+	{
+		return s_lfoInstances;
+	}
 
 	void fillLevel( float * _buf, f_cnt_t _frame,
 				const f_cnt_t _release_begin,
@@ -89,8 +118,7 @@ protected:
 
 
 private:
-	static QVector<EnvelopeAndLfoParameters *> s_EaLParametersInstances;
-
+	static LfoInstances * s_lfoInstances;
 	bool m_used;
 
 

src/core/EnvelopeAndLfoParameters.cpp

@@ -1,8 +1,8 @@
 /*
  * EnvelopeAndLfoParameters.cpp - class EnvelopeAndLfoParameters
  *
- * Copyright (c) 2004-2008 Tobias Doerffel <tobydox/at/users.sourceforge.net>
- * 
+ * Copyright (c) 2004-2010 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ *
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
  * This program is free software; you can redistribute it and/or
@@ -38,7 +38,53 @@ extern const float SECS_PER_ENV_SEGMENT = 5.0f;
 extern const float SECS_PER_LFO_OSCILLATION = 20.0f;
 
 
-QVector<EnvelopeAndLfoParameters *> EnvelopeAndLfoParameters::s_EaLParametersInstances;
+EnvelopeAndLfoParameters::LfoInstances * EnvelopeAndLfoParameters::s_lfoInstances = NULL;
+
+
+void EnvelopeAndLfoParameters::LfoInstances::trigger()
+{
+	QMutexLocker m( &m_lfoListMutex );
+	for( LfoList::Iterator it = m_lfos.begin();
+							it != m_lfos.end(); ++it )
+	{
+		( *it )->m_lfoFrame +=
+				engine::getMixer()->framesPerPeriod();
+		( *it )->m_bad_lfoShapeData = true;
+	}
+}
+
+
+
+
+void EnvelopeAndLfoParameters::LfoInstances::reset()
+{
+	QMutexLocker m( &m_lfoListMutex );
+	for( LfoList::Iterator it = m_lfos.begin();
+							it != m_lfos.end(); ++it )
+	{
+		( *it )->m_lfoFrame = 0;
+		( *it )->m_bad_lfoShapeData = true;
+	}
+}
+
+
+
+void EnvelopeAndLfoParameters::LfoInstances::add( EnvelopeAndLfoParameters * lfo )
+{
+	QMutexLocker m( &m_lfoListMutex );
+	m_lfos.append( lfo );
+}
+
+
+
+
+void EnvelopeAndLfoParameters::LfoInstances::remove( EnvelopeAndLfoParameters * lfo )
+{
+	QMutexLocker m( &m_lfoListMutex );
+	m_lfos.removeAll( lfo );
+}
+
+
 
 
 
@@ -70,7 +116,12 @@ EnvelopeAndLfoParameters::EnvelopeAndLfoParameters(
 	m_lfoAmountIsZero( false ),
 	m_lfoShapeData( NULL )
 {
-	s_EaLParametersInstances.push_back( this );
+	if( s_lfoInstances == NULL )
+	{
+		s_lfoInstances = new LfoInstances();
+	}
+
+	instances()->add( this );
 
 	connect( &m_predelayModel, SIGNAL( dataChanged() ),
 			this, SLOT( updateSampleVars() ) );
@@ -133,10 +184,12 @@ EnvelopeAndLfoParameters::~EnvelopeAndLfoParameters()
 	delete[] m_rEnv;
 	delete[] m_lfoShapeData;
 
-	QVector<EnvelopeAndLfoParameters *> & v = s_EaLParametersInstances;
-	if( qFind( v.begin(), v.end(), this ) != v.end() )
+	instances()->remove( this );
+
+	if( instances()->isEmpty() )
 	{
-		v.erase( qFind( v.begin(), v.end(), this ) );
+		delete instances();
+		s_lfoInstances = NULL;
 	}
 }
 
@@ -187,35 +240,6 @@ void EnvelopeAndLfoParameters::updateLfoShapeData()
 
 
 
-void EnvelopeAndLfoParameters::triggerLfo()
-{
-	QVector<EnvelopeAndLfoParameters *> & v = s_EaLParametersInstances;
-	for( QVector<EnvelopeAndLfoParameters *>::iterator it = v.begin();
-							it != v.end(); ++it )
-	{
-		( *it )->m_lfoFrame +=
-				engine::getMixer()->framesPerPeriod();
-		( *it )->m_bad_lfoShapeData = true;
-	}
-}
-
-
-
-
-void EnvelopeAndLfoParameters::resetLfo()
-{
-	QVector<EnvelopeAndLfoParameters *> & v = s_EaLParametersInstances;
-	for( QVector<EnvelopeAndLfoParameters *>::iterator it = v.begin();
-							it != v.end(); ++it )
-	{
-		( *it )->m_lfoFrame = 0;
-		( *it )->m_bad_lfoShapeData = true;
-	}
-}
-
-
-
-
 inline void EnvelopeAndLfoParameters::fillLfoLevel( float * _buf,
 							f_cnt_t _frame,
 							const fpp_t _frames )

src/core/mixer.cpp

@@ -1,8 +1,8 @@
 /*
  * mixer.cpp - audio-device-independent mixer for LMMS
  *
- * Copyright (c) 2004-2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
- * 
+ * Copyright (c) 2004-2010 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ *
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
  * This program is free software; you can redistribute it and/or
@@ -22,7 +22,6 @@
  *
  */
 
-
 #include <math.h>
 
 #include "mixer.h"
@@ -664,7 +663,7 @@ const surroundSampleFrame * mixer::renderNextBuffer()
 	emit nextAudioBuffer();
 
 	// and trigger LFOs
-	EnvelopeAndLfoParameters::triggerLfo();
+	EnvelopeAndLfoParameters::instances()->trigger();
 	Controller::triggerFrameCounter();
 
 	const float new_cpu_load = timer.elapsed() / 10000.0f *

src/core/song.cpp

@@ -1,7 +1,7 @@
 /*
- * song.cpp - root of the model-tree
+ * song.cpp - root of the model tree
  *
- * Copyright (c) 2004-2009 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ * Copyright (c) 2004-2010 Tobias Doerffel <tobydox/at/users.sourceforge.net>
  *
  * This file is part of Linux MultiMedia Studio - http://lmms.sourceforge.net
  *
@@ -300,7 +300,7 @@ void song::processNextBuffer()
 			// at song-start we have to reset the LFOs
 			if( m_playPos[Mode_PlaySong] == 0 )
 			{
-				EnvelopeAndLfoParameters::resetLfo();
+				EnvelopeAndLfoParameters::instances()->reset();
 			}
 			break;