From 446486da6b37c52a89ec991f92d4826ce14c8be8 Mon Sep 17 00:00:00 2001
From: Frits Talbot <frits@metapathy.com>
Date: Mon, 25 Aug 2014 23:09:39 +0200
Subject: [PATCH] Delete leaking params that cause JUCE assertions to fail. Fix
 bad MidiMessage construction (JUCE assertion failure). Workaround for Cubase
 7.5 invoking setCurrentProgram after setStateInformation and overwriting
 saved state with hardcoded preset. Add rudimentary versioning to
 get-/setStateInformation.

---
 Source/PluginProcessor.cpp | 71 +++++++++++++++++++++++++++++++++-----
 Source/PluginProcessor.h   |  1 +
 2 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/Source/PluginProcessor.cpp b/Source/PluginProcessor.cpp
index ea71510..91f5b7e 100644
--- a/Source/PluginProcessor.cpp
+++ b/Source/PluginProcessor.cpp
@@ -6,6 +6,7 @@
 
 //==============================================================================
 JuceOplvstiAudioProcessor::JuceOplvstiAudioProcessor()
+	: i_program(-1)
 {
 	// Initalize OPL
 	velocity = false;
@@ -380,6 +381,8 @@ void JuceOplvstiAudioProcessor::applyPitchBend()
 
 JuceOplvstiAudioProcessor::~JuceOplvstiAudioProcessor()
 {
+	for (int i = 0; i < params.size(); ++i)
+		delete params[i];
 }
 
 //==============================================================================
@@ -598,6 +601,9 @@ void JuceOplvstiAudioProcessor::updateGuiIfPresent()
 
 void JuceOplvstiAudioProcessor::setCurrentProgram (int index)
 {
+	if (i_program==index)
+		return;
+
 	i_program = index;
 	std::vector<float> &v_params = programs[getProgramName(index)];
 	for (unsigned int i = 0; i < params.size() && i < v_params.size(); i++) {
@@ -634,7 +640,7 @@ void JuceOplvstiAudioProcessor::processBlock (AudioSampleBuffer& buffer, MidiBuf
 	buffer.clear(0, 0, buffer.getNumSamples());
 	MidiBuffer::Iterator midi_buffer_iterator(midiMessages);
 
-	MidiMessage midi_message(0);
+	MidiMessage midi_message;
 	int sample_number;
 	while (midi_buffer_iterator.getNextEvent(midi_message,sample_number)) {
 		if (midi_message.isNoteOn()) {
@@ -678,9 +684,9 @@ void JuceOplvstiAudioProcessor::processBlock (AudioSampleBuffer& buffer, MidiBuf
 			while (ch <= Hiopl::CHANNELS && n != active_notes[ch]) {
 				ch += 1;
 			}
-			Opl->KeyOff(ch);
-			active_notes[ch] = NO_NOTE;
-		}
+				Opl->KeyOff(ch);
+				active_notes[ch]=NO_NOTE;
+			}
 		else if (midi_message.isPitchWheel()) {
 			int bend = midi_message.getPitchWheelValue() - 0x2000;	// range -8192 to 8191
 			// 1.05946309436 == (2^(1/1200))^100 == 1 semitone == 100 cents
@@ -704,22 +710,71 @@ AudioProcessorEditor* JuceOplvstiAudioProcessor::createEditor()
 	return gui;
 }
 
+// FIXME: these two funcs and get-/setStateInformation should be replaced by a proper cross-platform archiving API, e.g. eos portable archive or boost text archive
+template<class T>
+void push(char *&cursor, T value)
+{
+	*reinterpret_cast<T *>(cursor) = value;
+	cursor+=sizeof(T);
+}
+
+template<class T>
+void pop(const char *&cursor, T &value)
+{
+	value=*reinterpret_cast<const T *>(cursor);
+	cursor+=sizeof(T);
+}
+
 //==============================================================================
 void JuceOplvstiAudioProcessor::getStateInformation (MemoryBlock& destData)
 {
-	destData.ensureSize(sizeof(float) * getNumParameters());
+	destData.ensureSize(sizeof(CURRENT_VERSION)+sizeof(i_program)+sizeof(float) * getNumParameters());
+
+	char *cursor = static_cast<char *>(destData.getData());
+
+	push(cursor, CURRENT_VERSION);
+	push(cursor, i_program);
+
 	for (int i = 0; i < getNumParameters(); i++) {
 		float p = getParameter(i);
-		destData.copyFrom((void*)&p, i*sizeof(float), sizeof(float));
+		push(cursor, p);
 	}
 }
 
 void JuceOplvstiAudioProcessor::setStateInformation (const void* data, int sizeInBytes)
 {
+	if (sizeInBytes < sizeof(CURRENT_VERSION))
+		return;
+
+	const char *cursor = static_cast<const char *>(data);
+	const char *end = cursor+sizeInBytes;
+	int version;
+	
+	pop(cursor, version);
+
+	if (version == CURRENT_VERSION)
+	{
+		pop(cursor, i_program);
+
+		const int parametersToLoad = std::min<int>(static_cast<int>(std::distance(cursor, end)) / sizeof(float), getNumParameters());
+
+		for (int i = 0; i < parametersToLoad; i++)
+		{
+			float p;
+
+			pop(cursor, p);
+			setParameter(i, p);
+		}
+
+		return;
+	}
+
 	float* fdata = (float*)data;
-	for (unsigned int i = 0; i < sizeInBytes / sizeof(float); i++) {
+	const int parametersToLoad = std::min<int>(sizeInBytes / sizeof(float), getNumParameters());
+
+	for (int i = 0; i < parametersToLoad; i++) {
 		setParameter(i, fdata[i]);
-	}	
+	}
 }
 
 //==============================================================================
diff --git a/Source/PluginProcessor.h b/Source/PluginProcessor.h
index e3cac2f..c7a95b2 100644
--- a/Source/PluginProcessor.h
+++ b/Source/PluginProcessor.h
@@ -88,6 +88,7 @@ private:
 	int i_program;
 	bool velocity;
 	static const int NO_NOTE=-1;
+	static const int CURRENT_VERSION = 0x09720100; // OPL2 v01.00 magic
 	int active_notes[Hiopl::CHANNELS+1];	// keyed by channel
 	float currentScaledBend;